Yes, it is "will have + past participle". It can also be "will have + been + present participle". The second one is future perfect progressive/continuous. I, also, do not care very much for using "be going to" as a future perfect form. It's a grammatical possibility, but I don't think it's too common. Using "will" sounds more natural to me.Originally Posted by valtango
This is my way of defining "future perfect".
· Future Perfect Aspect
· Future Perfect Continuous/Progressive Aspect
We can think of the future perfect and future perfect progressive/continuous as follows:
1. The future perfect expresses future events and actions in relationship to other future events and actions.
2. The future perfect shows how one event or action in the future corresponds in time to another event or action in the future.
· The future perfect is used when we want to show how one event in the future is related to another event in the future.
· There is often some sort of reason for wanting to compare when one thing will happen to when another thing will happen.
· The events to take place may be thought of as important in some way by both the speaker and the listener.
· The events to take place don’t have to, necessarily, be important.
· When using the future perfect, it is often possible to use another future form to express the same thing. It is the importance of how two events coincide with each other that often compels the speaker to use the future perfect or the future perfect progressive/continuous.
Future Perfect Aspect Examples
The elevator was out of order Monday night. There was a sign that instructed us to use the staircase, but the door to the staircase was locked. Someone came down at about 6:25 and we were able to go up to the second floor. If the elevator is not repaired by Wednesday, we have to be sure that the door to the staircase is not locked.
· Hopefully, they’ll have fixed the elevator by then.
· Hopefully, the elevator will have been fixed by Wednesday.