What is the use of past perfect tense?

Answer 1

The past perfect tense is used to keep time relationships straight. When you are talking about some past event, past perfect is for time before that.

Let's say you're talking about the birth of baby Jill. She was born at some past time. When you speak of anything before her birth while you are talking about her birth, you use the past perfect to refer to that earlier time. For example:

Jill was [past] born in 2005.

When Jill was [past] born, her parents had been [past perfect] trying to get pregnant for two years.

Now suppose you are writing a story all in the past tense, and you want to talk about events before the story began. It might go like this:

Once there was [past] a little boy named Jack who had lived [past perfect] on a farm all his life. Now he had [past] his first chance to visit a city. He was [past] so excited! He had never seen [past perfect]tall buildings before.