GMAT Tip: Punctuation Pointers

This tip on improving your GMAT score was provided by Vivian Kerr at Veritas Prep.

Punctuation is and isn’t tested on the GMAT. While a sentence-correction question will never require you to outrightly list all the proper usages of a semicolon, you will need to know how clauses are formed by pieces of punctuation to modify different words and phrases within a sentence. For example, we already know that a modifying clause introduced by the word “which” should be preceded by the comma. Let’s take a quick look at the punctuation you’re likely to see on test day, then examine a harder sentence correction question.

Comma: These guys are all over the place on the GMAT. Commas are used to set apart non-essential information. Comma usage is always tied to meaning: Essential modifiers will never be set apart by commas.

Semicolon: The semicolon is like a Swiffer; it tends to tidy up long, unclear sentences. Use a semicolon between two independent clauses; an independent clause is another way of saying a complete sentence, or a complete thought. Sometimes semicolons can be used to separate items in a list if the items themselves already contain commas.

Colon: The colon is used to set up a definition or explanation. The clause that sets up the explanation (either prior to the colon, or after the colon) should be able to stand on its own as a complete sentence. Think of it as you would approach a joke: One side of the colon is the “set up” and the other side is the “punchline.”

Dash: The dash has been becoming more and more common on the GMAT, used in pairs to set apart non-essential information with a dash in front of and after the phrase (just like a comma), or used to indicate a break in thought.

Let’s look at a complicated problem involving lots of punctuation:

Almost all philosophers seem to agree that matter is in fact “real”: they generally conclude that, however much our sense-data—color, shape, texture, etc.—may depend upon us, their very occurrence is  a sign of something existing independently of us, something differing, perhaps, completely from our sense-data, and yet to be regarded as causing that sense-data. 

The verbosity of this sentence alone is enough to make any test-taker’s head spin, but let’s focus in on the three pieces of punctuation: colon (:), dash (—), and comma (,).

Surprisingly, the colon, dashes, and commas are all used correctly. The colon introduces the definition of the concept “real,” and the dashes and commas correctly set apart nonessential information. In addition, the plural “their” correctly refers to the plural “data.” (“Datum” is singular.) While definitely wordy, there are no errors in grammar, style, or meaning.

Always remember to ask yourself: how is this piece of punctuation changing the meaning of the sentence? If you’re feeling confused, try to imagine the sentence without the punctuation and see if it still makes sense. And remember, you can strategically use punctuation to your advantage: Where there are pairs of commas or dashes, see if you can skip the nonessential information in between to focus on things such as subject-verb or pronoun agreement. Where there is a semicolon in one or more answer choices, check the other choices to make sure they’re not run-on sentences in need of a semicolon.

In language, punctuation serves as signals to a reader for how to organize the words logically. Similarly on the GMAT, punctuation can be a signal telling you what the author of the question deems important (or unimportant), providing a valuable clue to the correct answer.

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