A punctuation question at the start of a sentence tests how the opening words connect to what follows. Read the sentence after the blank, then ask whether the opening words can stand alone. Cross out possible extra information to check that you still have a complete sentence. An opening description takes a comma; a semicolon needs complete sentences on both sides. Keep words that form one phrase together, since a pause alone doesn't call for punctuation.
Hints
- Hint 1
Read from “the giant sequoia” to the end. Check whether those words can stand alone as a sentence.
- Hint 2
Find the boundary of the opening phrase, then ask whether that phrase can stand alone or describes the subject that follows.
Step-by-step
Test the opening phrase
Step 1Find the complete sentence
Read the giant sequoia can live more than three thousand years and continue through the words about its height. Does the sentence work without any opening words? Yes: the giant sequoia is what the sentence is about, and can live and grow tell us what it can do. Since those words already make a complete sentence, the punctuation depends on whether the opening words add a description or form a sentence of their own.
- Step 2
Test the opening words
All the choices begin with Evolving, so what job does that word do? It describes how the giant sequoia developed; unlike can live, it can't serve as the main verb on its own. The words over millions of years tell us how long the sequoia took to evolve, so they belong directly with Evolving. Together, these words make one opening description, not a separate complete sentence, and we can cross them out without breaking the sentence about how long the tree lives and how tall it grows.
- Step 3
Mark the description’s end
At the giant sequoia can live, the opening description ends and the main part of the sentence starts, so one comma closes the description. The start of the sentence takes care of its other end, which means this phrase doesn't need a pair of marks. The version Evolving over millions of years, keeps the words together and puts the comma where the main part begins. Choice B.