We will have cleared that area before the new construction begins. We will have cleared that area before the new construction begins.
Jim will have been working for the company for 20 years next week. The company is giving him a gold watch.
The future perfect simple is sometimes referred to as 'the past in the future' as it is used to talk about an action or event from a future viewpoint.
The future perfect continuous is used to talk about an action that will continue up to a specified future time.
affirmative: subject + 'will' +'have' + past participle I will have eaten.
negative: subject + 'won't' + 'have' + past participle I won't have eaten
interrogative: 'will' + subject + 'have' + past participle Will you have eaten?
affirmative: subject + 'will' +'have' +'been'+ present participle I will have been working.
negative: subject + 'won't' + 'have' + 'been' + present participle I won't have been working.
interrogative: 'will' + subject + 'have' + 'been' + present participle Will you have been working?
=====Uses of the future perfect simple=====
| Uses | Examples |
|
When the action occurs before another action or specified time
|
By this time next week I'll have finished writing my report.
Will you have eaten before you go out?
We won't have finished the project by the deadline.
|
|
To express duration with stative and some mixed verbs
|
Mr. Cook will have had the report for a week by the time he reads it.
She will have been in Tokyo for a month when we visit her.
How long will I have owned this car when I have it re-sprayed next week?
|
|
Reflecting on past or current experiences or a plan
|
If I do nothing else, at least I will have written this novel.
|
| Making deductions about past or present events or situations | Don't worry - I'm sure Karen will have called him yesterday to cancel it.
There's no point calling him on his office number - he'll have gone to lunch. |
As with all future tenses the future perfect is not used in clauses that start with time expressions such as 'when', 'after', 'before' and 'as soon as'. In this case, use the present perfect.
When I will have finished work, I'm playing football with John. 
When I've finished work, I'm playing football with John. 
Will you have graduated before your next birthday?
We will have had the baby by the time your parents fly over from Australia. 
Do you think that the polar ice caps will have melted by 2050?
I'm sure it will have stopped raining by the time you get here.
You'll have been waiting for me for over two hours by the time my train gets in.
How long will you have been studying English for by the end of this course?
She'll have been travelling for over 24 hours by the time she gets here so she's going to be very tired.
=====Casual speech =====
There is a second contracted form which is considered very informal and should only be used in informal spoken English:
I'll've
You'll've
He'll've
She'll've
It'll've
We'll've
They'll've
In formal conversations or formal writing, use the full form.
In informal conversations or informal writing, use the contracted form.
=====Uses of the future perfect continuous=====
Uses | Examples |
To talk about an action that will continue up to a specified future time.
|
By this time next week I'll have been travelling for three days.
|
To talk about something that we assume is happening at the moment.
|
You should go home now; your parents will have been worrying about you all day.
|
To talk about an action that we believe has been happening recently. [It's not about the future.]
|
Bankers will have been asking themselves if it was a good idea to relax the rules on mortgage lending or not.
|
A 'specified future time' is often indicated with the use of 'by', examples:
- by Wednesday
- by three o'clock
- by the time he gets here
- by this time next year