A punctuation question tests whether the words around a blank can stand alone as sentences. Split at the blank and check who or what each side is about and what it does or is. Then ask whether one part depends on another because of its opening word. An opening part that can't stand alone takes a comma, while a semicolon joins full sentences. A colon follows a full sentence and introduces an explanation.
Hints
- Hint 1
Look at the first word of the sentence as you split after winter. Does that word let the opening part stand alone, or make it wait for more?
- Hint 2
Read the words beginning with it melts on their own. Then ask whether the punctuation needs to join two full sentences or attach opening words to a full sentence.
Step-by-step
Split and test each part
Step 1Test the opening words
The opening words When snow blankets the Sierra Nevada mountains in end with winter in every choice, so split there to test the punctuation. Can this part stand alone? Snow does the blanketing, but When leaves us waiting to learn what happens at that time. The opening part depends on what follows.
- Step 2
Test the words after the blank
What happens when the snow covers the mountains? The choices supply it before melts gradually during spring and summer, giving us it melts. This can stand alone because it says what the snow does and has no word making it depend on another part. The words after the blank make a full sentence.
- Step 3
Attach the opening part
An opening part beginning with When takes a comma before the full sentence. A semicolon needs full sentences on both sides, and a colon needs a full sentence before it, so neither can follow this opening part. The version winter, it gives the needed comma. Choice D.