5. He said to me he hadn't finished his work.
6. Linda said she had to go home to make the dinner.
7. My best friend said to me he had just received a postcard from his aunt.
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- Câu gián tiếp dạng tường thuật: S1+ said/told+ to sb/ sb+ (that)+ S2+ V(lùi thì)
- Câu 5, 7: thì hiện tại hoàn thành-> lùi sang quá khứ hoàn thành
- Câu 6: must-> had to