14, He said that Mai would leave Ho Chi Minh city unless she found a good job.
=> Câu gián tiếp: will -> would; hiện tại đơn -> quá khứ đơn.
15, He said that they would have to hurry or they would be late for class.
=> Câu gián tiếp: “will” -> “would”
16, My boss said that his wife had been ill, so our visit to Japan had been delayed.
=> Câu gián tiếp: quá khứ đơn -> quá khứ hoàn thành
17, Bill said that some days ago his brother had had an accident.
=> Câu gián tiếp: quá khứ đơn -> quá khứ hoàn thành