Which Vs. That

Which Vs. That

Do you ever get confused about when to use that and when to use which?

Consider the following examples:

  • Ice cream, which is delicious, melts quickly in the summer heat.
  • The book that I’m reading is my favourite.
  • She got a failing grade on her test, which is too bad.

Can you figure out which which should stay which? If not, don’t worry: that which is at first confusing can still be learned! Now, that’s a statement that is inspirational. Or should I say “which is inspirational”?

Restrictive and Non-restrictive Clauses

To get to the bottom of which which stays which and which that stays that we have to first understand restrictive and non-restrictive clauses.

Restrictive Clauses

A restrictive clause is essential to the meaning of the sentence. In other words, you can’t get rid of it without changing what the sentence means. With a restrictive clause, use the word that.

  • Example: The test that you failed is important to your overall mark in this course.

When you remove “that you failed” the meaning of the sentence changes — it could be about any test in the course instead of the specific test that you failed. Don’t worry, we’re using the general “you” here. We’re sure that you, reading this post, have never failed any language tests, especially if you’re enrolled in one of LRDG’s language training programs.

Now, back to our regular programming: Are you clear on restrictive clauses? Let’s review a few more of them just to be sure:

  • The mirror that you broke is expensive. It’s not just any old mirror that’s expensive – it’s the one you broke (oops!)
  • The activists are working to overturn a law that allows dog owners to leave their dogs’ poop on the sidewalk. The specific information about the law the activists are trying to overturn is important to the sentence

Non-Restrictive Clauses

A non-restrictive clause is anything that can be removed without changing the meaning of the sentence. In other words, it’s extra!


  • There are cookies, which are delicious, in the oven. Of course, all cookies are delicious and so “which are delicious” is not information that is crucial to the overall meaning of the sentence. Bonus: I hope you noticed that in the previous sentence I wrote “that is crucial” instead of “which is crucial.” If you didn’t, no cookies for you!
  • The little boy’s pet hamster died, which is sad. In what world is a pet dying not sad? Thus, “which is sad” is extra information.


Now that you’re an expert on which which to use at which time, look at the list of examples that’s at the beginning of this post. Which ones are correct?

If you guessed that all of them are, congratulations!