1 she has been working on the problem all her life
has she?
2 the students have been translating the text for two hours
have they?
3 it has been snowing since midninght
has it?
4 he has been writing the novel for seven years
has he?
5 i have been doing sums for two hours
have you?
6 jane has been collecting postcards for twenty years
has he?
7 i have been waiting for them for half and hour
have you?
