giup minh 2b nay voi aaaa

5.

1. had returned

2. had never played

3. Had they already called

4. had never been

5. had worked

6. had flied

6.

1. had been living

2. had been teaching

3. Had they already called

4. hadn't been walking

5. had you been digging

6. had been playing

*Giải thích:

→ Cấu trúc thì quá khứ hoàn thành (past perfect):

(+) S + had + V3/ed

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

(?) Had + S + V3/ed?

→ Cấu trúc thì quá khứ hoàn thành tiếp diễn (past perfect continuous):

(+) S + had + been + Ving

(-) S + hadn't + been + Ving

(?) Had + S + been + Ving?

1.had returned 

2.had never played

3.had they al ready called

4.had never been

5.had worked

6.had flied

------------------------------------------

=> cấu trúc quá khứ hoàn thành :

(+) S + had + V3/-ed + O

(-) S + had not + V3/-ed + O

(?) Had + S + V3/-ed + O

=> DHNB:

- by the time 

- by the time  of

- when

- before

- after

- hardly , scarely ,barely ....

6.

1.had been living

2.had been teaching

3.had she been waiting 

4.hadn't been walking

5.had you digging 

6.had been playing 

------------------------------------------

=> Cấu trúc quá khứ hoàn thành tiếp diễn :

(+) S + had + been + V-ing

(-) S + had + not + been + V-ing

(?) Had + S + been + V-ing

DHNB :

- for

-since 

-when 

-how long

- until then 

-by the time

-before , after