This article explains how to build the Past Perfect Tense and how to use it. If you want to know how to build the Past Participle - an important part of the Past Perfect - read the "Past Participle" article.
How to Form the Past PerfectBasic Rule: "had" + past participle of the verb
He had owned many cars.
She had visited her parents once before.
Past Perfect - Passive VoiceBasic Rule: "had" + "been" + past participle of the verb
He had already been caught stealing twice.
They had been evicted several times before.
How to Use the Past PerfectThe past perfect is used for actions lying further back than other past actions.
I bought myself a cinnamon bun. (past action)
I hadn't eaten anything all day. (this talks about the time before I bought the cinnamon bun)
A lot of the time, the past perfect part offers an explanation for what happened later.
I had eaten a whole chicken (explanation), so I felt sick that night.
However, this is not always the case. The main point is that the past perfect describes what lies before the past simple.
I had spent all morning at home before I went to the hospital.
When certain points in time are mentioned (yesterday, three years ago, last week), the past perfect can still be used, but it is also possible to use the simple past instead.
Last Monday after I had mowed the lawn around noon, I went to the beach.
Last Monday after I mowed the lawn around noon, I went to the beach.