6. It is the first time I have met a famous singer.

7. It is the first time she has been ti the ballet.

8. We last saw Tom when he hadn't moved to Bristol 

9. The last time it wore that shirt was at Barbara's wedding.

6.it is the first time I have met such a famous singer

7.it is the first time I have been to the ballet

8.we last saw Tom when he moved to Bristol

9. The last time I wore that dress was at Barbara's wedding

+last time + S + Verb(ed/PI) +…+ was + khoảng thời gian + ago

= S + Last + Verb(ed/PI) + khoảng thời gian + ago

= S + have/ has + not + Verb(PII)+…+ for + khoảng thời gian

=  It + is + khoảng thời gian + since + S + Verb 

+This is the first time + S + have/has + P2: Lần đầu làm gì

=S +have/has + never + P2 + before

= S+ have/has not + P2 + before