The following passage is adapted from an essay about early twentieth-century astronomy. Which punctuation mark must be placed in the blank to properly connect the two independent clauses?
Answer:In the early twentieth century, Swedish astronomer Knut Lundmark was among the first to argue that some nebulae are actually distinct galaxies located far outside our own Milky Way. To support this claim, Lundmark analyzed the brightness of novae in the Andromeda Galaxy【;】 he concluded that Andromeda was millions of light-years away, a distance far greater than the size of our galaxy.
Answer
A semicolon (;) is the correct punctuation mark to place in the blank to separate the two independent clauses.
A semicolon is correct because it links two closely related independent clauses without the need for a coordinating conjunction. In the passage, both the segment before the blank and the segment after the blank contain a subject and a verb and express a complete thought, meaning they are independent clauses.
Step-by-Step Solution
Key Concept
Using semicolons to connect independent clauses