`\text{16. bought }`

$\rightarrow$ QKD - last week - V2

`\text{17. bought }`

$\rightarrow$ QKD - việc mua TV mới đã xảy ra trong QK rồi - V2

`\text{18. has watched }`

$\rightarrow$ HTHT - several times - S số ít - has - V3

`\text{19. watched }`

$\rightarrow$ QKD - last night - Ved

`\text{20. has met }`

$\rightarrow$ HTHT - before - S số ít - has - V3

`\text{21. met }`

$\rightarrow$ QKD - yesterday - V2

`\text{22. went }`

$\rightarrow$ QKD - last summer - V2

`\text{23. has never gone }`

$\rightarrow$ HTHT - never - S số ít - has - V3

`\text{24. has finished }`

$\rightarrow$ HTHT - recently - S số ít - has - V3

`\text{25. finished}`

$\rightarrow$ HTHT - three days ago - Ved

16.Bought

→last week⇒Thì QKĐ

17.Bought

⇒Thì QKĐ

18.Has watched

→several times⇒Thì HTHT

19.Watched

→last night⇒Thì QKĐ

20.Has met

→before⇒Thì HTHT

21.Met

→yesterday⇒Thì QKĐ

22.Went

→last summer⇒Thì QKĐ

23.Has never gone

→never⇒Thì HTHT

24.Has finished 

→recently⇒Thì HTHT

25.Finished

→ago⇒Thì QKĐ