Đáp án:

7. She asked Nam if his sister and brother went to the same school.

8. She asked her mum if there were any oranges in the fridge.

9. She asked Ba if he had been reading that book at 8 o'clock the previous Sunday.

10. He asked his friend if it would rain the following morning.

11. The teacher asked me where my father worked.

12. She asked Lan how many people there were in her family.

13. Tom's friend asked him how long he would stay in England.

14. The teacher asked Lan what her hobby was.

Giải thích: 

$-$ Quy tắc lùi thì:

$+$ Present simple (Hiện tại đơn) → Past simple (Quá khứ đơn)

$+$ Present continuous (Hiện tại tiếp diễn) → Past continuous (Quá khứ tiếp diễn)

$+$ Present perfect (Hiện tại hoàn thành) → Past perfect (Quá khứ hoàn thành)

$+$ Past simple (Quá khứ đơn) → Past perfect (Quá khứ hoàn thành)

$+$ Present perfect continuous (Hiệu tại hoàn thành tiếp diễn) → Past perfect continuous (Quá khứ hoàn thành tiếp diễn)

$+$ Past continuous (Quá khứ tiếp diễn) → Past perfect continuous (Quá khứ hoàn thành tiếp diễn)

$+$ will → would 

$+$ can → could 

$-$ Đổi từ chỉ thời gian:
$+$ tomorrow → the following day / the next day

$+$ tomorrow morning → the following morning

$+$ last Sunday → the previous Sunday

$+$ this → that

$-$ Đổi đại từ phù hợp ngữ cảnh: your → his/her, ... 

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