`8,` hadn't studied

`9,` had left

`10,` had broken

`11,` had drunk

`12,` hadn't locked

`13,` had hidden

`14,` had forgotten 

`15,` had never visited

`16,` had taken

`-` `-` `-` `-` `-` `-` `-` 

${\text{Giải thích: }}$

`@` Cấu trúc quá khứ hoàn thành:

(`+`) S `+` had `+` V3/V-ed..

(`-`) S `+` hadn't `+` V3/V-ed

(`?`) Had (not) `+` S `+` V3/V-ed..?

`-` DHNB: before, after, by the time, when, by the end of + tgian trong qk, until, by,... 

`->` Diễn tả hành động xảy ra trước một hành động khác trong quá khứ (thường kết hợp với qkđ).

                         $\color{pink}{\text{kieuank:3}}$

Quá khứ hoàn thành :

Diễn tả hành động đã xảy ra trong quá khứ và kết thúc trước một hành động quá khứ khác

`(+)` S + had + PII

`(-)` S + hadn't + PII

`(?)` Had + S + PII ?

---

8. hadn't studied

9. had left

10. had broken (By the time + QKHT + QKD)

11. had drunk

12. hadn't locked

13. had hidden

14. had forgotten

15. had never visited (QKHT + until + QKD)

16. had taken