Examkin

Question

Difficulty: MediumModal Auxiliaries and Expressing Modality

Despite the severe drought affecting the entire province, the agricultural cooperative recorded an unprecedented crop yield; they __________ adopted the newly introduced soil-moisture retention technique. Which modal auxiliary phrase correctly completes the sentence to express a logical deduction about a past event?

  1. must haveAnswer
  2. B
    must to have
  3. C
    might can have
  4. D
    oughted to have

Answer

The correct phrase is 'must have', which forms the modal past perfect to express a strong logical deduction about a completed past action.
The modal phrase 'must have' correctly expresses a logical deduction or high degree of certainty regarding a past action based on clear circumstantial evidence.

Step-by-Step Solution

1
Analyze the context of the sentence
The context provides strong evidence (an unprecedented crop yield during a severe drought) pointing to a logical conclusion about a past event.
Identifying sentence context determines the intended modality (e.g., possibility, obligation, or logical deduction).
2
Select the appropriate modal structure for past logical deduction
The structure 'modal verb (must) + have + past participle (adopted)' is required.
Logical deduction regarding past events requires the perfective modal structure without extra infinitive markers or double modals.
3
Eliminate ungrammatical verb forms
Reject forms with superfluous 'to' infinitives, double modals, or incorrect verb inflections.
Modal auxiliaries in English are defective verbs that cannot be inflected with '-ed' or combined directly with other modal verbs.

Key Concept

Modal Auxiliaries expressing past logical deduction
Rate this question

Topics

Modal Auxiliaries and Expressing Modality

More questions from this topic