1. He asked me how long I had studied English.
-> Câu trần thuật nên lùi thì từ hiện tại hoàn thành về quá khứ hoàn thành, thay đổi "you" thành "I" cho phù hợp
2. They tole me that they would have a picnic the next day.
-> Chuyển "tomorrow" thành "the next day", lùi "will" thành "would"
3. They said that they were going to take care of that baby the next month.
-> "next month" chuyển thành "the next month", chuyển "are" thành "were"
4. Lan asked Nam if he had been there the day before.