Răspuns:
1-B. have been friends
2-A: has been using?
3-B: have been working
4-B: has lost
5-A: have always believed
6-A: has been teaching
7-A: has opened
8-B: have not tasted
9-B: have been looking
10-B: have been cleaning
11-B: has drunk
12-B: have just moved