Form
Subject + had + V3
The man had walked the dog before it rained.
We had eaten dinner before they arrived.
Meaning
Action Before Another Past Point
Used for an action that was completed at some point before another event or time in the past. The earlier action is in the Past Perfect, the later reference is usually Past Simple or a time expression.
PastPresentFuture
x
x
She had finished her homework when he arrived.
They had eaten before the movie started.