6. He hasn't gone fishing before.
7. I haven't eaten that food since I lived in the city.
8. I haven't seen her since last Sunday. 
9. The last time Lan wrote to Maryam was last month.
10. It is 5 years since he watched cartoons. 
11. This is the first time I have met her. 
12. He has been cooking since 4.30PM.
13. When did you buy this car?
14. How long have you started listening to classical music?
15. I haven't seen her for 10 years.