10 i have never eaten that kind of food before.
-> thì HTHT
-> ta có cấu trúc : S + have / has + VPII
11 i haven't played chess since 1990
-> thì HTHT
-> ta có cấu trúc : S + have / has + VPII
12 It's the first time I have met such a famous singer.
-> ta có cấu trúc it's the first time : It’s the first time S + have/has Ved/V3.
13 my friend's mother started teaching english in this school a long time ago
-> sau start có thể + v-ing
14 this is the first time she has been angry
