What is the difference between the perfect tense and pluperfect tense?
The perfect tense indicates that an action was/is/will be completed before some other action.
The pluperfect indicates that the action was completed before some other action in the past.
The pluperfect (sometimes called the past perfect) is a perfect verb tense form describing an action completed before some other past action.
We had washed the dishes before Mother came home.
We have washed the dishes.
We will have washed the dishes before Mother gets home.