16 When did you leave the office yesterday? I left at about 8.30 yesterday.
17 was the weather cold yesterday? Yes, it was.
18 She stopped smoking two years ago.
19 They went to Germany when he was only 4.
20 Have you ever found any money in the street?
21 Who invented the telephone?
22 James hasn't finished his homework yet.
23 I have already cleaned the flat.