A: John was absent this morning. Do you know why?
B: No. I have no idea.
A: He told me (that) he had caught a bad cold.
B: How come.
A: He said (that) he had jumped into the water to help a drowning boy.
B: How brave of him!
A: Yes. And he had taken the boy to the hospital, too.
说明：1. 过去完成时由助动词had+过去分词构成。had用于各人称。2. 过去完成时常表示一个过去某一动作之前已经完成的动作。