Examkin

Sentence Structure and Formation

444 questions

All types444Multiple choice368Ordering15Fill in the blank61
Question 201Question →

The root systems of desert cacti, which are shallow but widespread to maximize water absorption, are much more extensive than a tropical rainforest plant.

Which choice best completes the sentence to ensure the comparison is logical and grammatically correct?

Show answer & explanation

Answer: those of tropical rainforest plants

Answer

The correct choice is 'those of tropical rainforest plants' because it uses the plural pronoun 'those' to refer back to 'root systems,' establishing a logical and grammatically parallel comparison.
The correct choice compares 'the root systems of desert cacti' to 'those of tropical rainforest plants' using the plural pronoun 'those' to refer to 'root systems.' This establishes a clear, parallel, and logical noun-to-noun comparison.

Step-by-Step Solution

1
Identify the two elements being compared in the sentence.
The sentence compares 'the root systems of desert cacti' to the underlined portion.
Comparing a physical feature ('root systems') to a whole organism ('a tropical rainforest plant') is illogical; the sentence must compare root systems to root systems.
2
Determine the correct pronoun to represent the comparison target without repeating the noun.
Since 'root systems' is plural, the plural pronoun 'those' must be used.
This ensures grammatical agreement and parallel structure in the comparison.
3
Evaluate the choices to find the one that establishes a logical comparison without introducing other grammatical errors.
The choice 'those of tropical rainforest plants' correctly uses 'those' to refer to root systems and avoids run-on or comma splice errors.
Other options either maintain the illogical comparison or introduce independent clauses incorrectly joined by a comma.

Key Concept

Illogical and Incomplete Comparisons
Question 202Question →

Read the passage below. To maintain consistency in grammatical construction and mood throughout the passage, what form of the verb 'stain' should be written in the blank?

Fill in the blanks below

When preparing a specimen for electron microscopy, first slice the tissue into extremely thin sections, and then rinse the sample with a buffering solution. Once the sample is prepared, it with a heavy metal stain to enhance the contrast of the cellular structures.
Show answer & explanation

Answer

stain
The passage establishes a sequence of instructions using the imperative mood ('slice' and 'rinse'). To maintain consistency in construction and mood, the blank must also use the imperative form of the verb. The base form 'stain' functions as a command, thereby preserving the parallel grammatical structure of the directions.

Step-by-Step Solution

1
Analyze the grammatical mood and construction of the preceding sentences and clauses in the passage.
The initial instructions use the imperative mood ('first slice... and then rinse...'), which issues direct commands without an explicit subject.
This establishes the established pattern of construction (imperative mood) for the instructional passage.
2
Identify the construction shift that would occur if other moods or structures were used.
Inserting indicative phrases like 'you should stain' or gerunds like 'staining' would shift the construction away from the imperative mood.
Maintaining consistent construction prevents a jarring shift in the author's tone and sentence structure.
3
Determine the correct form of the target verb 'stain' that maintains the imperative mood.
The base form 'stain' functions as an imperative verb, maintaining parallel construction with 'slice' and 'rinse'.
This completes the sentence while preserving grammatical consistency throughout the passage.

Key Concept

Shifts in Construction (Mood Consistency)
Question 203Question →

To correct the dangling modifier in the sentence, complete the blank with the logical subject that performs the action of the introductory phrase. Choose either 'the students' or 'the laboratory tables'.

Fill in the blanks below

Having finished the chemistry lab experiment, wiped down the workspace with disinfectant.
Show answer & explanation

Answer

the students
The introductory phrase 'Having finished the chemistry lab experiment' describes an action that must be performed by a logical agent. The students are capable of finishing an experiment, so placing 'the students' immediately after the modifying phrase correctly associates the modifier with its subject.

Step-by-Step Solution

1
Identify the introductory modifying phrase and the action it describes.
The introductory phrase is 'Having finished the chemistry lab experiment,' which describes the action of completing an experiment.
An introductory participial phrase must modify the subject that directly follows it.
2
Determine which noun logically performs this action.
The students are the logical agents who can perform and finish a chemistry experiment.
Placing 'the laboratory tables' immediately after the comma would create a dangling modifier, because tables cannot perform or finish an experiment.

Key Concept

An introductory modifying phrase must be immediately followed by the noun it logically modifies to avoid a dangling modifier.
Question 204Question →

To prepare a healthy garden, a gardener first tills the soil and clears out any weeds. Next, the gardener added compost to enrich the soil before planting the seeds. Finally, watering the beds regularly ensures that the plants grow strong.

Which of the following options, if substituted for the underlined word, best maintains a consistent verb tense in the passage?

Show answer & explanation

Answer: adds

Answer

adds
The correct answer is the word 'adds' because it is in the simple present tense. This matches the tense of the other verbs in the passage—'tills,' 'clears,' and 'ensures'—maintaining a consistent and logical timeframe throughout.

Step-by-Step Solution

1
Analyze the verbs in the surrounding sentences of the passage to identify the established timeframe.
The verbs 'tills' and 'clears' in the first sentence and 'ensures' in the third sentence are all in the simple present tense.
Establishing the dominant tense of the passage is necessary to recognize any inconsistent shifts in construction.
2
Evaluate the underlined verb 'added' against the established present-tense timeframe.
The verb 'added' is in the past tense, which represents a shift in construction from the present tense used elsewhere.
An unnecessary shift in verb tense disrupts the flow and logic of the passage.
3
Select the option that corrects this shift by putting the verb in the simple present tense.
The word 'adds' is in the simple present tense and matches the grammatical construction of the other sentences.
Using the present tense maintains consistency and ensures grammatical agreement across the entire passage.

Key Concept

Avoiding unnecessary shifts in verb tense to maintain grammatical consistency within a passage.
Estimated Time:40s
Question 205Question →

Restoring damaged peatlands is a critical component of global carbon management strategies, as these ecosystems store twice as much carbon as all the world's forests combined. When peatlands are drained for agriculture, the exposed organic matter decomposes rapidly, releasing massive volumes of carbon dioxide. Conservationists are now blocking drainage ditches to rewet the soil, consequently, this intervention, which raises the water table, halts the decay process.

Which of the following choices best corrects the underlined portion of the passage?

Show answer & explanation

Answer: soil; consequently, this intervention, which raises the water table, halts

Answer

The correct answer is the choice that uses a semicolon to separate the two independent clauses and keeps the active verb 'halts': 'soil; consequently, this intervention, which raises the water table, halts'.
The correct choice uses a semicolon to separate two independent clauses ('Conservationists are now blocking drainage ditches to rewet the soil' and 'consequently, this intervention, which raises the water table, halts the decay process') and correctly includes the finite verb 'halts' to complete the second clause.

Step-by-Step Solution

1
Analyze the first clause starting with 'Conservationists' to determine if it is independent.
The clause 'Conservationists are now blocking drainage ditches to rewet the soil' contains a subject ('Conservationists') and a verb ('are blocking') and expresses a complete thought, making it an independent clause.
Identifying clause boundaries is necessary to determine proper punctuation between clauses.
2
Analyze the second clause starting with 'this intervention' to check for independence and verb presence.
The clause 'this intervention, which raises the water table, halts the decay process' contains a subject ('this intervention') and a main verb ('halts'), separated by a non-restrictive relative clause ('which raises the water table'). It is also an independent clause.
Determining if the second clause is independent helps identify if a coordinating conjunction, semicolon, or period is needed.
3
Evaluate how the two independent clauses are joined and correct the grammatical error.
Joining two independent clauses with a comma and the conjunctive adverb 'consequently' creates a comma splice. A semicolon must be used before 'consequently' to correctly join them, and the verb 'halts' must remain a finite verb to avoid creating a fragment.
A semicolon is required to separate two independent clauses when no coordinating conjunction (FANBOYS) is present.

Key Concept

Run-on Sentences and Comma Splices
Question 206Question →

In 1965, chemist Stephanie Kwolek synthesized a new polymer solution that was unusually thin and cloudy. Although other researchers might have discarded the mixture because it did not look promising, Kwolek insisted on testing it; this decision ultimately led to the invention of Kevlar.

Which choice best completes the sentence while maintaining standard English punctuation and clause structure?

Show answer & explanation

Answer: NO CHANGE

Answer

NO CHANGE
The correct option is correct because the subordinating conjunction 'Although' properly establishes a relationship of contrast between the two parts of the first sentence. The dependent clause is correctly followed by a comma and the main independent clause, forming a grammatically sound unit that can be linked to the next sentence with a semicolon.

Step-by-Step Solution

1
Analyze the structure of the original sentence to determine the relationship between the clauses.
The sentence contains two main parts separated by a semicolon. The first part, which is underlined, consists of a dependent clause starting with 'Although' followed by an independent clause. The second part after the semicolon is another independent clause ('this decision ultimately led to the invention of Kevlar').
Understanding clause boundaries helps identify whether the punctuation and conjunctions are used correctly.
2
Evaluate the grammar of the underlined portion in the original sentence.
The subordinating conjunction 'Although' correctly makes the first clause dependent, which is then properly joined to the main independent clause ('Kwolek insisted on testing it') with a comma. This creates a grammatically complete independent unit before the semicolon.
This confirms that the original phrasing is grammatically correct and requires no modification.
3
Verify why the alternative options are incorrect.
Using a semicolon after the 'Although' clause creates a fragment. Removing 'Although' creates a comma splice between two independent clauses. Using 'Since' and 'and' makes the entire first part a dependent fragment.
Evaluating all options ensures that the distractors are incorrect for specific, identifiable grammatical errors.

Key Concept

Subordination and Coordination
Question 207Question →

In 1977, oceanographers aboard the research vessel *Alvin* made a startling discovery at the Galapagos Rift: they found hydrothermal vents spewing mineral-rich water into the ocean. Although these vents exist in complete darkness under crushing pressure; yet they support thriving ecosystems powered by chemosynthetic bacteria.

Which of the following choices best replaces the underlined portion of the sentence?

Show answer & explanation

Answer: Although these vents exist in complete darkness under crushing pressure, they

Answer

Although these vents exist in complete darkness under crushing pressure, they
The correct answer properly resolves the sentence structure by removing the redundant coordinating conjunction and using a comma to separate the introductory dependent clause from the main independent clause. This maintains the logical relationship of contrast without introducing punctuation or coordination errors.

Step-by-Step Solution

1
Identify the clause boundaries and types within the sentence.
The first clause ('Although these vents exist...') is a dependent clause due to the subordinating conjunction 'Although'. The second clause ('they support thriving ecosystems...') is a complete independent clause.
Determining clause types is necessary to select the appropriate coordinating or subordinating conjunctions and punctuation.
2
Evaluate the punctuation and conjunctions connecting the clauses in the original sentence.
A semicolon is used to separate the dependent clause from the independent clause, which is grammatically incorrect. Additionally, 'Although' (subordinating) and 'yet' (coordinating) are both used, creating a double-conjunction error.
Semicolons can only connect two independent clauses, and using two conjunctions to connect the same two clauses is redundant.
3
Evaluate the choices to find one that correctly connects the clauses without punctuation errors or redundancy.
The correct option removes the coordinating conjunction 'yet' and uses a comma instead of a semicolon to connect the introductory dependent clause to the independent clause.
An introductory dependent clause must be followed by a comma before joining the main independent clause.

Key Concept

Subordination and Coordination
Question 208Question →

Deep-sea hydrothermal vents, which were first discovered in 1977 near the Galápagos Rift, support complex ecosystems in complete darkness. Here, bacteria generate energy by oxidizing hydrogen sulfide. A process known as chemosynthesis, which forms the foundation of a food web that sustains giant tube worms and ghost crabs.

Which of the following options represents the most grammatically correct replacement for the underlined portion?

Show answer & explanation

Answer: Here, bacteria generate energy by oxidizing hydrogen sulfide through a process known as chemosynthesis,

Answer

Here, bacteria generate energy by oxidizing hydrogen sulfide through a process known as chemosynthesis,
The correct option resolves the fragment by converting the separate noun phrase into a prepositional phrase ('through a process') that modifies how the bacteria generate energy. This smoothly links the main clause to the relative clause beginning with 'which,' creating a single, grammatically correct sentence.

Step-by-Step Solution

1
Analyze the structure of the underlined portion and the sentence context.
The original text divides the thought into two sentences. The first sentence is complete, but the second sentence starting with 'A process' is a noun phrase followed by a relative clause and lacks a main verb.
Identifying sentence fragments requires checking if each punctuated sentence contains both a subject and a verb and forms a complete thought.
2
Evaluate the choices to find a version that resolves the fragment.
Replacing the period with 'through a process' links the chemical process directly to the verb 'oxidizing,' integrating all clauses into a single grammatically correct sentence.
Converting a fragment into a modifier or linking it to the main clause is an effective way to fix sentence fragment errors.
3
Verify that the other choices do not introduce new grammatical errors.
The semicolon choice creates a punctuation fragment, and the choice adding 'it forms' creates a comma splice.
Distractors must be checked for run-on sentences, comma splices, and incorrect punctuation usage.

Key Concept

Sentence Fragments
Question 209Question →

Deep-sea hydrothermal vents support extraordinary ecosystems by releasing mineral-rich fluids into the ocean. Although these environments exist in complete darkness under crushing pressure. They host unique communities of tube worms, giant clams, and chemosynthetic bacteria.

Which of the following choices is the most grammatically correct option for the underlined portion?

Show answer & explanation

Answer: Although these environments exist in complete darkness under crushing pressure, they

Answer

Although these environments exist in complete darkness under crushing pressure, they
The correct option connects the introductory dependent clause starting with 'Although' to the independent clause using a comma. This resolves the sentence fragment and creates a grammatically correct sentence.

Step-by-Step Solution

1
Identify the grammatical problem in the underlined portion.
The clause 'Although these environments exist in complete darkness under crushing pressure' begins with the subordinating conjunction 'Although' and lacks an independent main clause, making it a dependent clause fragment.
A dependent clause cannot stand alone as a complete sentence.
2
Evaluate the choices to find the one that correctly integrates the dependent clause.
The option that changes the period to a comma and adds the pronoun 'they' correctly joins the dependent clause to the subsequent independent clause.
Using a comma to connect an introductory dependent clause to an independent clause forms a grammatically correct complex sentence.
3
Rule out the remaining distractors.
The option using a semicolon is incorrect because a semicolon cannot connect a dependent clause to an independent clause. The option without 'Although' is a comma splice because it connects two independent clauses with only a comma.
Semicolons must separate two independent clauses, and independent clauses cannot be joined with just a comma.

Key Concept

Identifying and correcting sentence fragments by properly connecting dependent and independent clauses.
Estimated Time:1m 0s
Question 210Question →

Many home bakers enjoy cultivating a sourdough starter, which is a mixture of flour and water that captures wild yeast. This starter requires daily feedings. Because the yeast needs a constant source of nutrients to survive.

Which of the following options is the best replacement for the underlined portion of the sentence?

Show answer & explanation

Answer: feedings because the yeast

Answer

feedings because the yeast
The correct option connects the dependent clause directly to the independent clause that precedes it. By removing the period and the capital letter, the fragment is resolved into a single, grammatically correct sentence.

Step-by-Step Solution

1
Identify the grammatical issue in the underlined portion and the sentence following it.
The phrase starting with 'Because' is a dependent clause, which makes it a sentence fragment when separated by a period.
Recognizing that a dependent clause cannot stand alone as a complete sentence is the first step in resolving fragments.
2
Evaluate the options to find one that connects the dependent clause to the preceding independent clause.
Removing the period and connecting the clauses directly is required.
Connecting a dependent clause to an independent clause eliminates the sentence fragment.
3
Ensure that the chosen option does not introduce other punctuation errors, such as semicolon fragments or comma splices.
The option without a period or semicolon, and retaining the subordinating conjunction, is grammatically correct.
Semicolons cannot precede dependent clauses, and joining two independent clauses with only a comma creates a comma splice.

Key Concept

Sentence Fragments
Question 211Question →

Complete the sentence to maintain parallel structure by writing the correct form of the verb 'renovate' in the blank.

Fill in the blanks below

The local council resolved not only to build a new public park but also the existing community center.
Show answer & explanation

Answer

to renovate
The correct answer is 'to renovate' because it maintains a parallel infinitive structure with 'to build' across the correlative conjunction 'not only... but also'.

Step-by-Step Solution

1
Identify the grammatical structure of the phrase following the first part of the correlative conjunction 'not only'.
The phrase 'to build' is an infinitive verb.
Correlative conjunctions require parallel grammatical structures on both sides of the conjunction.
2
Select the form of 'renovate' that matches the infinitive structure following 'but also'.
The parallel form is 'to renovate'.
Since the first element is the full infinitive 'to build', the second element must also be the full infinitive 'to renovate' to maintain parallelism.

Key Concept

Parallelism with correlative conjunctions requires that the grammatical structure following 'not only' matches the structure following 'but also'.
Estimated Time:1m 0s
Question 212Question →

In the sentence below, the writer wants to maintain a consistent present-tense construction. Fill in the blank with the correct form of the verb 'rise' to ensure grammatical consistency.

Fill in the blanks below

Every morning, the birds sing loudly outside my window, and the sun over the horizon.
Show answer & explanation

Answer

rises
The verb 'sing' in the first clause establishes that the actions are happening in the present tense. To avoid an unnecessary shift in construction, the verb in the second clause must also be in the present tense. Since the subject 'the sun' is singular, the correct present-tense form is 'rises'.

Step-by-Step Solution

1
Identify the tense of the established verb in the sentence.
The verb 'sing' in the first clause is in the present tense, establishing a present-tense frame for the habitual morning routine.
To maintain consistency and avoid an unnecessary shift in construction, the verb in the second clause must also be in the present tense.
2
Determine the subject of the second clause and apply the correct present-tense verb form.
The subject of the second clause is 'the sun' (third-person singular), which requires the singular present-tense form 'rises'.
Using any other tense or incorrect subject-verb agreement would violate grammatical consistency.

Key Concept

Maintaining consistent verb tense to avoid shifts in construction within a sentence.
Question 213Question →

The atmospheric conditions of Mars, which feature thin air and global dust storms, are far more hostile to human life than Earth.

Which of the following is the best replacement for the underlined portion of the sentence?

Show answer & explanation

Answer: those of Earth

Answer

The correct option is 'those of Earth', which logically compares the atmospheric conditions of Mars to the atmospheric conditions of Earth using the plural pronoun 'those'.
The correct option replaces the underlined portion with 'those of Earth.' This creates a logical and grammatically parallel comparison because the plural pronoun 'those' correctly refers back to 'atmospheric conditions,' thereby comparing the atmospheric conditions of Mars to the atmospheric conditions of Earth.

Step-by-Step Solution

1
Identify the elements being compared in the sentence.
The sentence begins by discussing 'The atmospheric conditions of Mars' (plural noun phrase) and compares them to 'Earth' (singular planet).
This helps determine if the comparison is logical and grammatically parallel.
2
Evaluate the grammatical logic of the comparison.
Comparing 'conditions' to a planet is illogical; we must compare 'conditions' to the 'conditions' of the other planet.
ACT English requires comparisons to be between similar types of nouns.
3
Select the pronoun that matches the plural subject being compared.
Since 'atmospheric conditions' is plural, the plural pronoun 'those' is needed (resulting in 'those of Earth').
Using 'those of' refers back to 'atmospheric conditions' and completes the comparison logically.

Key Concept

Illogical and Incomplete Comparisons
Question 214Question →

In 1925, at the age of fifty-five, botanist Ynes Mexia embarked on her first collecting expedition to Mexico. She traversed steep mountainsides and remote forests, eventually collecting thousands of specimens. Although she faced rugged terrain and frequent mudslides, but she successfully gathered over five hundred species of plants on her inaugural trip alone.

Which of the following is the best revision of the underlined portion of the sentence?

Show answer & explanation

Answer: Although she faced rugged terrain and frequent mudslides, she successfully gathered

Answer

The option stating 'Although she faced rugged terrain and frequent mudslides, she successfully gathered' is the correct answer.
The correct option properly uses the subordinating conjunction 'Although' to set up a contrast in a dependent clause, which is correctly separated from the main independent clause by a comma. This creates a grammatically sound complex sentence.

Step-by-Step Solution

1
Identify the relationship between the two clauses in the sentence.
The first clause describes a obstacle ('faced rugged terrain and frequent mudslides') and the second clause describes an achievement ('successfully gathered over five hundred species of plants'), indicating a contrast relationship.
Recognizing the logical relationship helps determine the correct conjunctions to use.
2
Analyze the grammar of the original underlined sentence structure.
The original sentence contains both the subordinating conjunction 'Although' and the coordinating conjunction 'but' to link a single dependent clause to an independent clause.
Using two contrasting conjunctions to join two clauses is a grammatical error known as a double conjunction.
3
Select the option that properly coordinates or subordinates the clauses.
Removing the coordinating conjunction 'but' leaves a subordinate clause followed by a comma and a main clause, which is grammatically correct and logically clear.
An introductory dependent clause starting with a subordinating conjunction must be followed directly by a comma and the independent clause with no additional coordinating conjunctions.

Key Concept

Subordination and Coordination
Question 215Question →

The following passage contains an underlined portion.

In environmental science, policy analysts frequently debate the efficacy of carbon taxation. While carbon taxes directly disincentivize industrial emissions, they can disproportionately affect low-income households <u>, consequently, implementing targeted rebates, that offset these costs,</u> is essential to ensure economic equity. These programs help maintain public support for climate initiatives while protecting vulnerable populations.

Which of the following is the best replacement for the underlined portion of the passage?

Show answer & explanation

Answer: ; consequently, implementing targeted rebates that offset these costs

Answer

The correct option is the one that uses a semicolon before the conjunctive adverb 'consequently' and removes the commas around the restrictive relative clause.
The correct option correctly uses a semicolon to link the two independent clauses and correctly avoids setting off the restrictive relative clause 'that offset these costs' with commas.

Step-by-Step Solution

1
Identify the clause boundary and structure.
The text before the underlined portion is an independent clause ('While carbon taxes... low-income households'), and the text following it is another independent clause ('implementing targeted rebates... is essential to ensure economic equity').
Determining if the clauses are independent is necessary to select the correct punctuation to join them.
2
Evaluate the punctuation needed to join the independent clauses.
The clauses are joined by the conjunctive adverb 'consequently'. A semicolon must precede 'consequently' to avoid a comma splice.
Joining two independent clauses with only a comma and a conjunctive adverb results in a comma splice error.
3
Analyze the relative clause 'that offset these costs' for commas.
The clause 'that offset these costs' is restrictive (essential to the meaning of 'targeted rebates'), so it must not be enclosed in commas.
Enclosing restrictive relative clauses in commas is grammatically incorrect because it falsely implies the information is parenthetical or nonessential.

Key Concept

Run-on Sentences and Comma Splices
Question 216Question →

The following passage is an excerpt from a history of the Brooklyn Bridge.

During the building of the Brooklyn Bridge in the late nineteenth century, workers faced dangerous conditions under the East River. Inside the massive timber caissons, laborers excavated silt, blasted bedrock, and a constant battle against decompression sickness was fought. Many workers emerged from the depths with severe joint pain, a condition they called "the bends."

Which of the following choices best corrects the underlined portion to maintain consistency in grammatical construction?

Show answer & explanation

Answer: fought a constant battle against decompression sickness

Answer

fought a constant battle against decompression sickness
The correct option maintains the active voice and past tense established earlier in the sentence. The sentence describes a list of actions performed by the subject 'laborers': they 'excavated silt,' 'blasted bedrock,' and 'fought a constant battle.' Using the active, past-tense verb 'fought' ensures grammatical parallelism and prevents an unnecessary shift in construction.

Step-by-Step Solution

1
Identify the structure of the sentence and the list of actions performed by the subject.
The subject 'laborers' performs a series of three actions: 'excavated silt,' 'blasted bedrock,' and the underlined portion.
Understanding the grammatical structure helps identify the pattern that the third item must follow.
2
Analyze the underlined portion to check for consistency in construction.
The original phrasing 'a constant battle against decompression sickness was fought' is in the passive voice with a new subject ('a constant battle'), shifting construction away from the active past-tense verbs 'excavated' and 'blasted'.
This identifies the error in the original sentence as a shift in grammatical construction and voice.
3
Evaluate the choices to find one that maintains active voice, past tense, and grammatical parallelism.
The phrasing 'fought a constant battle against decompression sickness' matches the past-tense active structure of 'excavated' and 'blasted' and keeps 'laborers' as the subject.
This resolves the construction shift and ensures parallel structure.

Key Concept

Avoiding shifts in construction and maintaining parallel structure in a list of verbs.
Question 217Question →

Read the following passage about ancient architecture:

Stepwells, unique subterranean water temples constructed across western India, served as vital water reservoirs. Because these structures descended deep into the earth. They also provided relief from the intense summer heat.

Which of the following options is the most grammatically correct revision of the underlined portion?

Show answer & explanation

Answer: Because these structures descended deep into the earth, they

Answer

The option that connects the dependent clause to the main clause using a comma: 'Because these structures descended deep into the earth, they'
The correct option properly connects the introductory dependent clause (which starts with the subordinating conjunction 'Because') to the main independent clause using a comma. This creates a unified and grammatically complete sentence.

Step-by-Step Solution

1
Analyze the grammatical structure of the underlined portion and the clause that follows it.
The clause 'Because these structures descended deep into the earth' begins with the subordinating conjunction 'Because,' making it a dependent clause that cannot stand alone as a complete sentence.
Identifying the clause type is necessary to determine if the punctuation creates a sentence fragment.
2
Determine the correct punctuation to link an introductory dependent clause to an independent clause.
An introductory dependent clause must be followed by a comma when it is joined to a subsequent main independent clause.
Using a period or a semicolon after a dependent clause leaves it disconnected, resulting in a grammatical fragment.
3
Evaluate the choices to find the option that correctly uses a comma to join the clauses without creating a comma splice.
The option containing 'Because these structures descended deep into the earth, they' correctly resolves the fragment by joining the dependent clause to the main clause with a comma.
This establishes a complete, grammatically sound sentence.

Key Concept

Resolving sentence fragments by properly joining an introductory dependent clause to an independent clause with a comma.
Question 218Question →

Gothic cathedrals are renowned for their soaring heights and stained-glass windows, which were made possible by the invention of the flying buttress. These stone arches, which channeled the lateral thrust of the roof outward. This structural innovation allowed builders to construct taller walls with larger openings.

Which of the following options is the best replacement for the underlined portion?

Show answer & explanation

Answer: These stone arches channeled the lateral thrust of the roof outward. This structural

Answer

The option that removes the relative pronoun 'which' and uses a period to separate the two independent clauses is correct.
The correct option removes the relative pronoun 'which', allowing 'channeled' to serve as the main verb of the subject 'These stone arches'. This successfully forms a complete independent clause that is correctly separated from the next sentence by a period.

Step-by-Step Solution

1
Analyze the underlined portion to determine if it functions as a complete sentence or a fragment.
The phrase 'These stone arches, which channeled the lateral thrust of the roof outward' contains a relative clause but has no main verb for the subject 'These stone arches', meaning it is a sentence fragment.
Every sentence must have at least one independent clause containing a subject and a verb.
2
Check the options to see how the fragment can be repaired.
Removing the relative pronoun 'which' makes 'channeled' the main verb of the clause, forming a complete independent clause. A period must follow this clause to separate it from the next independent clause.
Correcting a fragment often involves removing subordinators to establish a clear subject-verb relationship.
3
Evaluate the remaining options to ensure they do not introduce new grammatical errors.
Using a comma instead of a period between the two clauses creates a comma splice. Using a semicolon before a participial phrase incorrectly isolates a fragment.
Ensuring the corrected sentence does not create comma splices or punctuation errors is necessary to identify the single best option.

Key Concept

Identifying and correcting sentence fragments by ensuring clauses contain a subject and an independent verb, while avoiding comma splices and semicolon errors.
Question 219Question →

In 1912, German meteorologist Alfred Wegener proposed the theory of continental drift, suggesting that the Earth's continents were once joined in a single supercontinent. Despite his peers ridiculed the idea for its lack of a driving mechanism; Wegener spent the rest of his life gathering geological and paleontological evidence to support his hypothesis.

Which choice best completes the sentence, establishing a logical and grammatically correct relationship between the clauses?

Show answer & explanation

Answer: Although his peers ridiculed the idea for its lack of a driving mechanism, Wegener

Answer

The correct option is the one starting with 'Although his peers...', which uses the subordinating conjunction 'Although' to set up a dependent clause and connects it to the main clause with a comma.
The correct option correctly uses the subordinating conjunction 'Although' to introduce a dependent clause ('Although his peers ridiculed the idea for its lack of a driving mechanism'), which is then correctly separated from the main independent clause ('Wegener spent...') by a comma. This creates a clear, grammatically correct transition showing contrast.

Step-by-Step Solution

1
Analyze the relationship between the two clauses.
The first clause describes the opposition Wegener faced ('his peers ridiculed the idea'), and the second clause describes Wegener's actions in response ('Wegener spent the rest of his life...'). This suggests a relationship of contrast or concession.
Identifying the logical relationship helps choose the correct subordinating or coordinating conjunction.
2
Evaluate the grammar of the original underlined portion.
The original text uses 'Despite' as a conjunction (which is incorrect since it is a preposition) and uses a semicolon to separate the clauses, which is incorrect because the first part is not an independent clause.
This helps determine if a change is needed.
3
Evaluate the remaining options for grammatical correctness.
The option beginning with 'Although' correctly sets up a dependent clause of concession and joins it to the independent clause with a comma. The option beginning with 'His peers' creates a comma splice. The option beginning with 'Because' and containing 'but' creates a sentence fragment.
This identifies the only grammatically correct and logically appropriate option.

Key Concept

Subordination and Coordination
Estimated Time:1m 0s
Question 220Question →

The museum's new curator aims not only to expand the contemporary art collection but also strengthening community outreach programs to engage local students.

Which choice best maintains the parallel structure of the sentence?

Show answer & explanation

Answer: to strengthen community outreach programs

Answer

to strengthen community outreach programs
The sentence uses the correlative conjunction structure 'not only... but also' to connect two parallel actions. The first action is introduced by the infinitive 'to expand' ('not only to expand the contemporary art collection'). To maintain parallel structure, the second action must also be in the infinitive form, 'to strengthen' ('but also to strengthen community outreach programs'). The correct option achieves this grammatical balance.

Step-by-Step Solution

1
Identify the coordinating or correlative conjunction structure in the sentence.
The sentence uses the correlative conjunction pair 'not only... but also'.
Correlative conjunctions require the phrases they connect to be grammatically parallel.
2
Analyze the grammatical structure of the phrase immediately following the first part of the conjunction ('not only').
The phrase 'to expand the contemporary art collection' begins with an infinitive ('to expand').
This establishes the grammatical pattern that the second part of the conjunction must follow.
3
Evaluate the choices to find the one that matches this infinitive pattern.
The phrase 'to strengthen community outreach programs' matches the infinitive pattern.
Using 'to strengthen' creates a parallel structure ('to expand... to strengthen') that is grammatically correct.

Key Concept

Parallel Structure
Estimated Time:1m 0s
PreviousPage 11 / 23Next
Sentence Structure and Formation Practice Questions — ACT — Page 11 | Examkin