The future perfect describes an action that will be finished or completed in the future.
The future perfect is formed by combining will have with the past participle:
You will have seen me walk across the stage.
They will have visited the museum.
Simply add not:
We will not have managed that.
Use the regular form:
Will he have gone home?
At the end of our trip we will have visited twenty countries.
I don’t think I will have completed the assignment by then.
As the examples show, the future perfect is often used to refer to an action completed before some other event or moment.
For more information, please see our introduction to all twelve verb tenses in English.