Phyllis Freeman asks about use of the past perfect in constructions such as have done and have gone.
We use the past perfect tense often in English, even without realizing it.
1. The words had and have show us it’s past perfect—meaning it’s action that was completed before something else took place in the past.
For example, Before Nellie visited (simple past) I had prepared (past perfect) the guest room. Preparing the room was done before Nellie arrived.
The past perfect refers to a time earlier than now and you use it to make it clear which happened first. Andy had saved his document before his computer crashed. Isn’t it obvious which took place (and was completed) before the second event?
2. We use past perfect to explain something that happened in the past.
I had eaten a big lunch so I wasn’t hungry at dinnertime. (Had eaten was completed before the evening meal.)
3. Occasionally we use the stative verb (a verb that refers to the state of being) to show something that began in the past but continues to another action in the more recent past.
When Maurice married Joan, he had lived in Liverpool nine years. (He had lived in Liverpool continuously or until he married, or even longer.)
4. We also use the past perfect when we speak conditionally or when something is contrary to fact.
Had I known you lived in this city, I would have visited you. (I didn’t know you lived here. Notice both verbs use the past perfect.)