4 Don't forget to check for spelling mistakes before you hand in your composition.
5 The children couldn't go swimming because the sea was too rough.
6 It is hours since Mary rang.
7 He didn't win the race.
8 Not until I looked at the room that I realized, had I turned off the cooker.
9 You don't know about cars as much as I do.
10 While I was walking in the country, the rain began to fall.