`wd.`

`@` Hiện tại hoàn thành `->` Quá khứ hoàn thành

`-` They say, "We have finished our homework."

`->` They said (that) they had finished their homework.

`@` Quá khứ đơn `->` Quá khứ hoàn thành

`-` He said, "I visited the museum yesterday."

`->` He said (that) he visited the museum the previous day.

`@` Quá khứ tiếp diễn `->` Quá khứ hoàn thành tiếp diễn

`-` She said, "I was reading when you called."

`->` She said (that) she had been reading when I called.

`@` Hoàn thành tiếp diễn `->` Quá khứ hoàn thành tiếp diễn

`-` She said "I have been reading for `2` hours".

`->` She said (that) she had been reading for `2` hours.