`1.` Lan said to me (that) she had gone to school late the day before.

`-` Thì quá khứ đơn `->` Thì quá khứ hoàn thành

`-` yesterday `->` the day before

`2.` Ba said to Nga (that) his son hadn’t done his homework the day before.

`3.` Nga said to Nam (that) her mother had sent him some books the night before.

`-` last night `->` the night before

`4.` He said to me (that) he hadn't been very tired the night before.

`5.` She said to her (that) she had been very tired the night before.

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Công thức`:` S + said (to)/ told + (O) + (that) + S + V(lùi thì)

`-` Thì quá khứ đơn`:`

Động từ thường:

$(+)$ S + Ved/ V2

$(-)$ S + did not/ didn't + Vinf

Động từ to be:

$(+)$ S + was/ were + N/ adj

$(-)$ S + was/ were + not + N/ adj

`-` Thì quá khứ hoàn thành:

$(+)$ S + had + V(pp)

$(-)$ S + hadn't + V(pp)

1. Lan said to me she had gone to school late yesterday.

2. Ba said to Nga his son hadn't done his homework yesterday.

3. Nga said to Nam her mother had sent him some books last night.

4. He said to me he hadn't been very tired last night.

5. She said to her she had been tired last night.