Viết lại câu 
1The last time we saw him was on  Monday
=>> We haven't gone to a cinema for 2 years
2 John hasn't had his hair cut for over six months
=>> John last had his hair cut over 6 months ago
3 How long have you studied medicine? 
=>> When did you start studying medicine?
4 We moved to this area 10 years ago
=>> We have moved to this area for 10 years
5 How long is it since you late saw Mary?
=>> How long have you seen Mary?
6 My father stopped smoking last year
=>> My father hasn't smoked since last year
7 How long have you been teaching at this schoo
=>> When did you teach at this school?
8 We have Learnt English for 4 years
=>> We started to learn english 4 years ago
9 My father started to give up smoking last yea
=>> My father has given up smoking since last year
10 They have worked in that factory since 2001
=>> Thay started to work in that factory in 2001