GMAT Idiom: That vs. Which

January 4, 2010

Few idioms are tougher to master than the proper usage of "that" and "which." It can be particularly tricky for native English speakers because the words are so commonly misused in everyday life.

Here's a handy way to remember the rule: "That" is restrictive, while "which" is non-restrictive. The rule will make more sense after some further discussion.

Consider two similar sentences:

1. I'm staying at the hotel in Chicago that the Andersons operate.
2. I'm staying at the hotel in Chicago, which the Andersons operate.

In the first sentence, the phrase "that the Andersons operate" changes the meaning of "the hotel in Chicago." If you remove the phrase "that the Andersons operate," you've altered the meaning of the sentence. While "the hotel in Chicago" could mean many different things, the phrase that follows "restricts" its meaning.

In the second sentence, the phrase "which the Andersons operate" is essentially background information. Grammatically speaking, we could remove the phrase "which the Andersons operate" and the meaning would not change.

That's your test to determine whether "that" or "which" is appropriate: Can the phrase be removed without changing the meaning of the sentence?

Next time you read a sentence that contains the word "that" or "which," try rewriting it with the other one. Subtle differences like these require more than just memorization. Put some thought into it, and you can internalize the concept.

About the author: Jeff Sackmann has written many GMAT preparation books, including the popular Total GMAT Math, Total GMAT Verbal, and GMAT 111. He has also created explanations for problems in The Official Guide, as well as 1,800 practice GMAT math questions.

• Sentence Correction: more articles
• All articles at GMAT Hacks
• Search GMAT Hacks

Total GMAT Verbal The comprehensive guide to the GMAT Verbal section. Recognize, dissect, and master every question type you'll face on the test. Everything you need, all in one place, including 100+ realistic practice questions. Click to read more.