9, started
10, was watching
11, get
12, will be
13, will answer
14, late/ had forgot (đề sai: không phải là “leave” mà là “late”. Ta có “late for work”: muộn làm)
15, got/ had been waiting
16, wrote
17, was crossing/ struck
18, took
19, were not doing/ was cooking/ was reading
20, had finished
21, We haven’t been to the cinema for a long time.
22, I haven’t seen Rose for three years.
23, It is three months since I visited the museum.
24, John has played the piano for 10 years.
25, I haven’t seen her for a week.
Exercise 15
1, A -> was walking
2, A -> had eaten
3, A -> were you doing
4, D -> had already left
5, C -> since
6, A -> disappeared
7, D -> cooked