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Non-Defining Relative Clauses


Practice 1: Should these sentences have commas or not? Choose non-defining relative clause if you think it needs commas (the information is extra) and defining relative clause if you think it doesn't need commas (the information is necessary).


Teachers who work in primary schools should get more money.



Google which started in 1998 is used to find information on the internet.



Websites which have games aren't allowed in my college.



She gave me a present which was very nice of her.



I went to Toronto which is the capital of Canada.



I don't like people who tell lies.




Practice 2: Who, which, that or nothing? Choose the best way to complete these sentences. Sometimes both answers are possible, so you should choose the last option - for example "the girl (who) I met yesterday is a rock star. ("who" is not necessary).


  • The clothes aren't dry yet.
  • The cat is really cute.
  • Mr Watson, , is a spy.
  • The food was disgusting.
  • My car, , has never broken down.
  • I hate peole
  • Tom's party, , was fantastic!!!
  • This website, , started in 2010.