$1$ `:` The girl said to her mother that she couldn't marry him that year.

`-` I `->` She / He / It

`-` This `->` That

`-` Can't `->` Couldn't

$2$ `:` I said to my room mate that my watch had been stolen.

`-` HTHT `->` QKHT

$3$ `:` My girl friend said to me that I looked happy that day.

`-` Today `->` That day

`-` HTĐ `->` QKĐ

$4$ `:` My sister said that she was going to the theatre the next day.

`-` Is / Are / Am going to `->` Was / Were going to

`-` Tomorrow `->` The next day

$5$ `:` My mother says to me that she will buy me a new dress.

`-` I `->` She / He / It

`-` S `+` say ( s ) `+` ( that ) `+` S `+` V `+` O.

`->` Cấu trúc này thì sẽ không lùi thì 

`-` Câu tường thuật `:`

`->` S `+` said `+` ( that ) `+` S `+` V `+` O.

* Câu tường thuật phải lùi thì

`\text{1.}`This girl said to her mother (that) she couldn't marry him that year

- can+V(inf)=> could+V(inf)

- this => that

`\text{2.}`I said to my roommate (that) her watch had been stolen

- your => her

- Bị động hiện tại hoàn thành => Quá khứ hoàn thành

`\text{3.}`My girl friend said to me (that) I looked happy that day

- you => I

- today => that day

- Hiện tại đơn => Qúa khứ đơn

`\text{4.}`My sister said (that) she was going to the theatre the next day

- I => She

- tomorrow => The next day

- Tương lai gần => was/were+ going to +V(inf)

`\text{5.}`My mother says to me (that) she will buy me a new dress

- you => me

- Cấu trúc câu gián tiếp với câu trần thuật: S+ said +(that)+S+V(lùi thì)

- Ở câu 5 "say" đang chia ở thì hiện tại đơn thì khi đổi sang câu gián tiếp ta chỉ đổi ngôi, không đổi thì của động từ và trạng từ