◇ The Past Perfect
過去完成式
過去完成式指出事件發生在比某過去時間點還更早的時候。此時態會被用在表明其中一個事件早於另一個發生。這和在文章中提及的順序無關，只要用過去完成式清楚說明哪一個先發生即可。
Example：
1. I had already started washing when I noticed the dirty shirt.
我都已經洗好衣服了，才發現有這件贓襯衫。
2. Luckily, he had already saved the document before his computer crashed.
幸運地，他早在電腦當機前把檔案都存起來了。
3. We had already left the house when you called to ask for a ride.
我們早在你要來搭便車之前就已經出發了。