The Future Perfect Tense denotes that something will have been finished at some future period.

A Few Models.

I shall have done my homework by nine. (Archaic.)

I will have done my homework by nine. (Modern.)

She will have done it.

He will have come there.

Note :- We often say things as this also :

They will have heard the news by now. (Certainty.)

They should have heard the news by now. (Probability.)

(“Will have” expresses Certainty, “Should have” expresses Probability.)

Homework.

Find some more illustrations and make/line/remember the Syntax (as in lessons nos. 76 and 77).