${21.}$ He told me he could see the Eiffel Tower from one of the windows of his flat.

${22.}$ David told us he wasn't enjoying his job very much.

${23.}$ She said that she was very busy.

${24.}$ He told me he would see me soon.

${25.}$ He told me he had to do his homework that night.

${26.}$ She said that she would phone the office from the airport.

${27.}$ He said that she didn't know what to do.

${28.}$ She said she was studyinh English then.

${29.}$ He said he had a toothache.

${30.}$ Lan said she would write him a letter.

→ S + said/ told sb/ said to sb (that) + S + V(lùi thì): câu gián tiếp dạng trần thuật

* Một số thì của động từ lùi thì:

- HTĐ → QKĐ

- HTTD → QKTD

- HTHT → QKHT

- HTHTTD → QKHTTD

- QKĐ → QKHT 

- QKTD → QKHTTD

- is/am/are going to → was/were going to

- can/ will/ shall/ may/ must + V0 → could/ would/ should/ might/ had to + V0

=>

21. He said to me that he could see the Eiffel Tower from one of the windows of his flat.

22. David said to uss that he was enjoying his job very much.

23. She said that she was very busy.

24. He said to me that he would see me soon.

25. He said to me that he had to do his homework that night.

26. She said that she would phone the office from the airport.

27. He said that he didn't know what to do.

28. She said that she was studying English then.

29. He said that he had a toothache.

30. Lan said that she would write him a letter.

Câu tường thuật -> lùi thì

Can -> Could 

HTTD -> QKTD

HTĐ -> QKĐ

Will -> Would

Must -> Had to

Một số từ/cụm từ chỉ thời gian :

Tonight -> That night

Now -> Then