GMAT Sentence Correction: Choosing Between Similar Words

A common point of confusion among those studying for the GMAT—as well as the general writing public—is the difference between several sets of similar but different words (that vs. which, if vs. whether, between vs. among, like vs. as). Knowing which of these words to use in a given situation can often allow you to eliminate a couple of answer choices, speeding up your verbal test-taking and ultimately helping to improve your score.
 

The simplest way to remember the difference is by noting that “which” introduces information that isn’t crucial to the meaning of the sentence, known as a non-restrictive or non-essential clause, while “that” introduces a restrictive clause. For example,
I am going to wear the sweater that is blue.
I am going to wear the sweater, which is blue.
In the former sentence, “that is blue” functions to restrict the meaning; the implication is that there is more than one sweater, but only one blue one, and the blue one is the one I’m going to wear. In the latter sentence, the phrase “which is blue” merely provides more information about the sweater. The sentence’s meaning wouldn’t change dramatically without the “which is blue,” because the information is non-essential.
An example of this kind of sentence on GMAT Sentence Corrections might look like this:

 
In this sentence, the meaning should be restricted; the diseases to which the sentence refers are specifically those that might have been fatal at one time. Therefore, the correct answer choice will use “that” instead of “which.” Choice A can therefore be eliminated, as can C and E. In addition, the structures of both C and E are sentence fragments; everything following “which” in those choices functions to describe “diseases,” leaving the sentence without a central verb. Choices B and D both use “that,” but choice B uses the wrong idiom: it says “prevented for” instead of “prevented by,” which changes the meaning of the sentence.
A second example might look like this:

 
Here, the adjective clause “has attracted a great deal of media coverage recently” should be non-restrictive. There is no indication that a specific kind of global warming will be a central issue. Instead, the sentence implies that global warming will be a central issue in the upcoming campaign, and “global warming” is further described as having “attracted a great deal of media coverage recently”. The meaning of the sentence would not be substantially changed by removing the information about media coverage. Therefore, “which” is appropriate in this sentence.  A and B can be eliminated for this reason; in addition, B can be eliminated because the future tense “will be attracting” is inconsistent with “recently.” Choice C has the same verb tense issue as choice B, and can therefore be eliminated. Choice D uses “being,” which is almost never correct on the GMAT, and also neglects to put the necessary comma after “coverage” at the end of the adjective clause. The final choice, E, does everything right: the verb tenses are appropriate, punctuation is correct, and “which” is properly used.
 

Remember

Separating restrictive and non-restrictive or non-essential clauses allows you to correctly choose whether to use “that” or “which” in GMAT Sentence Corrections, and like most grammar issues, it becomes much easier with practice.

 

A common misconception is that “if” and “whether” can be used interchangeably. However in some sentences using one or the other can subtly change the meaning of the sentence.
I wasn’t sure whether Joe wanted to play tennis or racquetball.
I wasn’t sure if Joe wanted to play tennis or racquetball.
In the first sentence using “whether” indicates the author is unsure which sport Joe wants to play. In the second sentence, using “if” indicates the author is unsure if Joe wants to play a sport at all.
Here are the specific rules governing the usage of these words. Generally “if” is used to describe a condition.
If you go to grocery store, pick me up some root beer and vanilla ice cream.
“Whether” is used to describe a choice.
Whether or not you go to the parade is up to you.
Okay, now what about “whether” versus “whether or not”? Answer: it depends on the context. Most of the time “or not” is unnecessary to the meaning of the sentence. If the meaning is clear without adding the “or not,” leave it out. Remember that concise answers are GMAT-friendly. Only keep the “or not” if it is unclear that there are two possibilities without it.
For the GMAT, here are a few more rules to keep in mind for “if” and “whether”:
1. If you need to imply a choice, the GMAT prefers “whether” (even though the use of “if” may seem grammatically correct).
-Lindsay can’t decide if she should buy the dress.
-Lindsay can’t decide whether she should buy the dress.
Here the GMAT would prefer the second sentence, since two choices are implied: that Lindsay should buy or should not buy the dress.
2. Use “whether” after prepositions (of whether, for whether, about whether, etc.)
3. Use “whether” before verbs in the infinitive form.
-Do you know whether to go out this late is a good idea?
 

Using Between Properly
Between is used with two people or things. You may notice the root tw appears in many words meaning “two” such as twice and twin.
Between is also used as part of a two-part idiom: “Between…and”
Between Jersey Shore and Dexter, I prefer Dexter.
Do not use the word “to” with “Between.”
INCORRECT: We took the airplane between New York to Paris.
Using Among Properly
Among is used for three or more people or things.
My choices were among Friday Night Lights, Mad Men, and 30 Rock.
Among can also indicate that someone is part or not part of a group.
He felt like a stranger among friends.
What About “Amongst”?
Amongst is an archaic form of among used in Britain but rarely in the United States. Though technically it can be used interchangeably with “among,” it is generally considered pretentious and old-fashioned. It would only appear in a specific antiquated context, such as: He found the king amongst his knights. You do not need to worry about “amongst” on the GMAT.
 

Using Like Properly
“Like” is used to compare two things. It can be used to be “similar to.”
Jo’s bike is just like Amy’s.
Like can also be used to mean “for example.”
She wanted a doll for Christmas, like Barbie or Skipper.
Using As Properly
“As” is used to link two ideas together.
Just as meditation is a form of relaxation, so yoga can provide stress-relief.
You will use “as” when the ideas you are comparing include a verb. This is because the word “as” can only be used to introduce a clause, not a phrase. Clauses include a subject and a verb. Notice that this sentence also included a two-part idiom: “Just as…so”
Another two-part idiom that uses “as” is the “as…as” idiom.
As soon as she got home, she took a nap.
Let’s look at this practice question question:

 
The answer is C. As written, “as” is modifying a prepositional phrase, “in campaign commercials.” This phrase lacks a verb. Choice C provides the verb “do” and completes the thought.