Giải giúp mình với ạ:

11. The teacher said We can collect old books for the poor students.

=>Hoa said

12. Where does your father work ?

=>the teacher asked me .

13 How much does this dress cost ?

=>Lan asked Lien .

14. What kind of books do you read ?

=>Thu asked Huong .

15. Do you see somebody using my book ?

=>Lan asked Thu .

16. John said "I have finished study my lesson"

=>John said

19. "I cannot go to the movie with you tonight, John"

=>Mary said

`11.` Hoa said they could collect old books for the poor students.

`-` Lùi thì: can `->` could

`12.` The teacher asked me where my father worked.

`-` Lùi thì: HTĐ `->` QKĐ

`13.` Lan asked Lien how much that dress cost.

`-` Lùi thì: HTĐ `->` QKĐ

`-` ĐTCĐ: this `->` that

`14.` Thu asked Phuong what kind of books she read.

`-` Lùi thì: HTĐ `->` QKĐ

`15.` Lan asked Thu if she saw somebody using her book.

`-` Lùi thì: HTĐ `->` QKĐ

`16.` John said that he had finished studying his lesson.

`-` Lùi thì: HTHT `->` QKHT

`19.` Mary said that she couldn't go to the movie with John that night.

`-` Lùi thì: can `->` could

`-` ĐTCTG: tonight `->` that night

`------------`

`@`Câu tường thuật:

`-` Kể: S + said (that) + S + V (lùi thì)

`-` WH question: S + asked sb + wh question + S + V (lùi thì)

`-` Yes/no question: S + asked sb + if/whether + S + V (lùi thì)