11 Have you read the book yet?
12 How many letters have they written so far?
13 When did he tell you that?
14 Were you at home last night?
15 How often have you travelled abroad till now?
16 He has just left his house.
17 We built a tree house last week.
18 Two years ago, Fiona broke her leg.
19 I have already washed the dishes.
20 The other day, our cat brought home a mouse.