English Grammar : The Use of Future Perfect Tense

Learn Grammar | English Grammar : The Use of Future Perfect Tense | Future perfect tense tells us that a certain action will be completed by a certain future time.

" Do you think we will have found papaya without seed in it by the end of this year?"

The certain time in the future is "by the end of this year". I am sure our botanist will have invented it before long, means at a certain time in the future (before long) our botanist will have invented it.

I shall have read this book by six o'clock tonight.This means that I have not yet read this book, but at six's o'clock tonight that is at a time in the future tonight, which is at a time in the future, the reading of the book will be past.

Observe the other examples :

• I shall have read seven of Erhan's plays by the end of this year.
• The football match may have finished if we do not hurry up.
• If nothing goes wrong. I shall have arrived in Bali Midday tomorrow.
• The leaves will have fallen from the trees after two months.
• The sun will have set by five o'clock this afternoon.

The pattern of the future perfect tense :
Subject + Will, May, Shall + Have + V-ed2 + O 
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