1. Having bought the cassette player, he found its defect.
After..........................................................................
2.Lying in the hammock,she was reading a novel
While she..................................................................
3.It's the first time that they have seen a big tiger
They...........................................................................
4.Mary has learnt Vietnamese for 5 years
It's..............................................................................
5.Thuy Tram has never been to HN before 
It's the first time.........................................................
6.We didn't belive him until be offered his presents 
It was not until..........................................................
7.We have not met our old teacher since last year
The last time...........................................................
8.Mrs.Lien has not gone to the market since Monday
The last time.................................................................
9.Before she went to bed.she had done her homework
After..........................................................................
10.As soon as she had come home,she cooked her meal
No sooner..................................................................