`1.` We had just heard the news when you rang.
`->` Câu ở QKHT, S + had + Ved/Vp.p + ... when + S + V(QKĐ)
`2.` I had already though of that before you suggested it.
`->` Câu ở QKHT, S + had + Ved/Vp.p + ...
`3.` When I turned on the TV, the programme had already started.
`->` Hành động chương trình xảy ra trước hành động bật TV `->` chia QKHT
`4.` She was hungry because hadn't eaten anything all day.
`5.` By the time I left school, I had decided to become a musician.
`->` By the time + S + V(QKĐ), S + had + Ved/Vp.p + ......