GMAT Tip: That vs. Which
The GMAT Tip of the Week is a weekly column that includes advice on taking the Graduate Management Admission Test, which is required for admission to most business schools. Every week an instructor from a top test prep company will share suggestions for improving your GMAT score. This week’s tip comes from Brent Hanneson, creator of GMAT Prep Now , a Web site offering on-demand videos that teach GMAT skills.
In this post we’ll examine the age-old dilemma of “that” vs. “which.” For example, which of these is correct?
A) Gina enjoys television shows that have laugh tracks.
B) Gina enjoys television shows, which have laugh tracks.
Here’s what you need to know.
A clause beginning with “that” is a restrictive clause. It takes a bunch of things and restricts the topic of discussion to a certain subset of those things. We use a “that clause” when the topic of discussion is unclear up to that point.
Conversely, a clause beginning with “which” is a non-restrictive clause. It does not attempt to restrict the topic of the discussion. We use a “which clause” when the topic of discussion is clear up to that point.
The first parts of the two sentences above read, “Gina enjoys television shows.” Up to this point, is the topic of discussion clear? Is this discussion about ALL television shows, or do we wish to restrict the discussion to a certain subset of television shows?
We want to restrict the discussion to just those television shows that have laugh tracks. As such, we need to use “that” to get “Gina enjoys television shows that have laugh tracks.”
So “that” functions as a sieve to filter out unwanted elements and limit the topic of discussion. Conversely, “which” doesn’t try to limit the discussion; it’s there to add color by providing additional, non-essential information.
For example, in the sentence, “Juan visited Lima, which is the capital city of Peru,” the clause “which is the capital city of Peru” adds color by telling us a bit more about Lima.
Now, the big problem with “that” vs. “which” is that it often requires us to know something about the nouns in a sentence. As such, it is unlikely that the GMAT would ever have a question that relies solely on the ”that” vs. “which” distinction.
Consider these two sentences:
A) My favorite painting is the Mona Lisa, which hangs in the Louvre.
B) My favorite painting is the Mona Lisa that hangs in the Louvre.
Which one is correct?
Well, it depends.
If there is only one painting in the world titled the Mona Lisa, then sentence A is correct, since the clause “which hangs in the Louvre” tells us a bit more about this one, unique painting.
If there were two or more paintings titled the Mona Lisa, then sentence B is correct, since we’d need to restrict the topic of conversation to one particular Mona Lisa. In other words, out of all the different paintings titled the Mona Lisa, my favorite is the one that hangs in the Louvre.
Brent Hanneson, the creator of GMAT Prep Now, has worked in the field of education for most of his career. He has taught courses at three different test-prep companies and created comprehensive GMAT and GRE ‘courseware’ packages used by the University of British Columbia and 12 other universities across North America.