Is it Which or That?

Are you confused about “which” versus “that?” You’re not the only one. We encounter this error every week when editing academic papers and other documents. Let’s take a closer look.

In order to understand which word to use, we must first understand two types of clauses: restrictive and non-restrictive.

A restrictive clause is a part of the sentence that cannot be removed. In other words, the meaning of the sentence would change if this clause were removed. On the other hand, a non-restrictive clause can be removed without changing the meaning of the sentence.

Now that we understand these two types of clauses, it is easy to determine when to use "which" versus "that."

1. Use "that" for restrictive clauses.

Here’s an example. Cars that rumble sound fast.

The restrictive clause is "that rumble." Without this clause, the sentence’s meaning is changed. In other words, cars sound fast because they rumble. If the clause of "that rumble" is removed, we know that all cars don’t sound fast.

2. Use "which" for non-restrictive clauses.

Here’s an example. The hurricane, which had winds up to 120 miles per hour, destroyed many homes and businesses.

The non-restrictive clause is "which had winds up to 120 miles per hour." In this sentence, if this non-restrictive clause is removed, the meaning of the sentence does not change. In other words, the hurricane still destroyed many homes and businesses, and this fact is unchanged by the winds of up to 120 miles per hour.

Put simply, use "that" when the clause is needed, and use "which" when the clause is expendable. It’s that easy!

Related Topics:

Word Battle: Who Vs. Whom
Word Battle: Effect Vs. Affect

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