_ © Paul Smit 2006-2022

Relative clauses

That and what relative clauses

We use that and what in some relative clauses. This can be confusing for some learners of English. Read the following conversation between four workers at a company where there has been an emergency. Note that what and that are not interchangeable in any of the sentences in this conversation.

Exercise 1:

  • Read the conversation.
  • Read the sentences again and change the words what and that in the sentences (in your head or on paper)
  • Think about why the two words cannot be changed.

Diego: I heard that there was a problem at work yesterday, but I didn’t hear what happened.

Sayif: I heard that there was a fire, but I don’t know what the cause was.

Miguel: Jane told me that it was caused by an electrical fault.

Michelle: John solved the problem because he did what I told him to do. I told him that he should first turn off the power and then use the fire extinguisher.

Diego: I wouldn’t have known what to do. I just know that I would have panicked.

Exercise 2:

  • Consider the following four sentences.
  • Decide which two are incorrect.
  • Check your answer by clicking “Show answer” below
  • Think about why they are incorrect.
  • Finally, select the correct rule.

a). She asked me what I’ve always dreamed of doing.

b). I answered: “Visiting Tibet is something that I have always wanted to do.

c). I was wondering that sort of car I would buy.

d). My wife said, “The car what you should buy should be small and economical.”


Sentence a) and b) are correct and sentences c) and d) are incorrect.

Exercise 3: Finding the rules

Exercise 4:

Complete the sentences in the activity below by writing “that” or “what” in the gaps.

-> Copyright © Paul Smit 2006-2023
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