A punctuation question with an added phrase tests where one full sentence ends and another begins. Read across the blank and test what can stand alone: find who or what each side is about and what happens. If a phrase adds a description, cross it out temporarily to see where the sentences meet. Two full sentences need a period, a semicolon, or a comma plus a joining word. A description near that join doesn't remove the need for a sentence boundary.
Hints
- Hint 1
Read from “That classification” onward and look for who or what each verb belongs to. Use those pairs to test whether the words on each side can stand alone.
- Hint 2
Temporarily cross out any added description and read the join that remains. What punctuation would that join need, and where does the description end?
Step-by-step
Find the sentences beneath the description
Step 1Test the words before the blank
Start with That classification remained influential to see whether the blank comes after a full sentence. Can this side stand alone once sites finishes it? The classification is the subject, which tells us what we're discussing. The main verb, remained, tells what happened to it. The after part adds timing to a full sentence.
- Step 2
Test the words after the blank
Now test microscopic wear patterns reveal: can this side stand alone? With patterns as the subject and reveal as its main verb, the following words complete another full sentence. Two full sentences need a boundary: a period, a semicolon, or a comma plus a joining word such as and.
- Step 3
Work out what the added phrase does
Each choice adds a result that surprised the excavators near the join. Is that a full sentence or an added description? Surprised belongs to that, which describes a result, so a result has no main verb of its own. It describes the fact that mixed assemblages were found, so it attaches to the first sentence. Cross it out temporarily, and the classification sentence still meets the sentence about wear patterns.
- Step 4
Put each mark where it belongs
A comma after sites attaches the description to the finding, but microscopic wear patterns reveal still needs a sentence boundary before it. Where should that boundary go? It goes after excavators, where the description ends, so use the comma first and the semicolon second. Choice B.