Past Perfect is used to describe an action that was completed at some point in the past before something else happened or to express that an action started and finished at a specific time in the past, but not to express something happening now at this very moment.

1. Question:
• When do we use Past Perfect?
Answer:
That an action was completed at some point in the
past before something else happened.
To express the idea that an action started and finished
at a specific time in the past.
To express the idea that something is happening now,
at this very moment.