`1,` We used to be made to clean the house by my mother

`->` BĐ - Used to : S + used to + be + P2 + (by O) ...

`2,` She said that she was working in a restaurant, and didn't care much for it

`->` CGT - Câu kể : S + said/told + (that) + S + V(lùi thì/đổi ngôi)

`->` Lùi thì : HTTD `->` QKTD ; HTĐ `->` QKĐ

`->` Đổi ngôi : I `->` she

`3,` I haven't spoken to her for two years

`->` It's + t/gian + since + S + last + V2/ed + ...

`=` S + have/has + not + P2 + ... + for + t/gian

`4,` It is interesting to go swimming in the river in the summer

`->` It's + adj + to V : Thật là như thế nào ... khi làm gì ...

`1.` We used to be made to clean the house by my mother

`-` be made to do sth : bị ai sai khiến làm gì

`2.` She said she was working in a restaurant, and didn't care much for it

`-` Câu gián tiếp dạng câu kể:

S + said + (that) + S + V(lùi thì)

`-` lùi thì: HTTD `->` QKTD ; HTĐ `->` QKĐ

`3.` I haven't spoken to her for two year

`-` It is  + time + since + S + last + V2/ed + O

`=` S + has/have + not + V3/ed + ... + time

`4.` It is interesting to go swimming in the river in the summer

`-` V_ing + ... +  tobe + adj

`=` It + tobe + adj + to_V + ...