When to Use That and Which


If you're learning English (or even if you're a native speaker!) the difference between 'that' and 'which' can be tricky to learn. It's a good thing then, that we're here to help! Read on to find out when to use these two words.
The quickest tip we can give you, is that if you take out the words following the word and it changes the meaning of the sentence, use 'that.' If the meaning doesn't change, use 'which.'
For example:
I don't like cats that bite. (If you take out the word 'bite,' the sentence would just mean that you don't like cats. But you just don't like cats that bite.)
Cats, which make great pets, can be silly sometimes. (If you take out the words 'which make great pets,' the essential meaning of the sentence doesn't change. You're just adding extra information.)
So What Does This Mean?
This rule is called a restrictive clause. A restrictive clause is a part of a sentence that you can't get rid of because it is essential to the sentence. If it was not in the sentence, it would completely change the meaning of the text. 
In the above example, 'that bite' is the restrictive clause. It also doesn't need commas around the restrictive clause.
On the other hand, 'which' is part of a non-restrictive clause. The information contained in it is not essential for the meaning of the sentence, and is just extra information. Also, non-restrictive clauses are usually surrounded by commas. This helps identify them as extra information.
In the example above, 'which make great pets' is the non-restrictive clause.
If you need any more help with your grammar points, don't hestitate to let us know! We'd be more than happy to set up English classes for you or your business. Give us a call or send us an email for more information!