$\text{1. }$My brother said (that) he was lunch with his class then.

- Lùi thì: Hiện tại đơn => Quá khứ đơn

- Đổi chủ ngữ: I => he

- now => then

$\text{2. }$My sister said she would do it later.

- Lùi thì: will+ V(inf) => would+ V(inf)

- Đổi chủ ngữ: I => she

$\text{3. }$Ann thanked Mary for giving her some fruit.

- Cấu trúc: S+ thank(ed) + Sb + for st/Ving: Cảm ơn ai vì làm gì

- Đổi tân ngữ: me => her

$\text{4. }$He asked me what my favourite color was.

- Lùi thì: Hiện tại đơn => Quá khứ đơn

- Đổi tính từ sở hữu: your => my

- Cấu trúc câu gián tiếp: 

+ Câu kể: S+ said+ (to O)+ (that)+ S+ V(lùi thì)

+ Wh-question: S+ asked+ O+ wh-question+ S+ V(ùi thì)

$\text{# themoonstarhk}$

`-` Tường thuật :

`=>` S + said + that + S + V ( lùi thì )

`-` Tường thuật NV ( Wh ) :

`=>` S + asked + O + wh + S + V ( lùi thì )

`-` HTĐ `->` QKĐ : S + Ved / V2 `-` S + was / were + adj / n

`-` TLĐ `->` TLTQK : S + would + V

`1`.My brother said that he was lunch with his class then

`2`.My sister said that she would do it later

`3`.Ann thanked me for giving her some fruit

`->` thank sb + for V-ing : Cảm ơn

`4`.He asked me what my favourite color was

`\text{# TF}`