The Future Perfect Continuous tense looks at the past from the future.

How do we make the Future Perfect Continuous Tense?

The structure of the Future Perfect Continuous tense is:

subject+auxiliary will+auxiliary have+auxiliary be+main verb
  invariable invariable past participle present participle
willhavebeenbase + ing

For negative sentences in the Future Perfect Continuous tense, we insert not between will and have . For question sentences, we exchange the subject and will . Look at these example sentences with the Future Perfect Continuous:

 subjectauxiliary verb auxiliary verbauxiliary verbmain verb 
+Iwill havebeenworkingfor four hours.
+Youwill havebeentravellingfor two days.
-Shewillnothavebeenusingthe car.
-Wewillnothavebeenwaitinglong.
?Willyou havebeenplayingfootball?
?Willthey havebeenwatchingTV?
We sometimes use shall  instead of will , especially for I and we.

Contraction with Future Perfect Continuous

In speaking with the Future Perfect Continuous tense, we often contract the subject and WILL:

I willI'll
you willyou'll
he will
she will
it will		he'll
she'll
it'll
we willwe'll
they willthey'll
  • I'll have been driving for five hours.
  • She'll have been watching TV.

In negative sentences, we may contract with won't , like this:

I will notI won't
you will notyou won't
he willnot
she will not
it will not		he won't
she won't
it won't
we will notwe won't
they will notthey won't
  • You won't have been drinking, will you?
  • We won't have been driving for long.

How do we use the Future Perfect Continuous Tense?

The Future Perfect Continuous tense is like the Future Perfect tense, but it expresses longer actions or states extending up to some specific event or time in the future . For example:

  • Ram starts waiting at 9am. I am late and cannot arrive before 10am. Ram will have been waiting for an hour by the time I meet him.
Ram  will have been waiting for one hour when I arrive.
pastpresentfuture
 Ram starts waiting at 9am.
 
 
 
 
 910
  I will arrive in future at 10am.

Notice that the long action or state can start at any time in the past, present or future , but of course it always ends in the future.

Next Monday we will have been living here for exactly five years.
pastpresentfuture
 
 
 next
Mon.
 5 yrs ago  

Look at these examples:

  • He'll be tired when he gets here. He'll have been travelling all day.
  • How long will Jo  have been working when he retires?
  • Next month I'll have been studying Chinese for two years.
  • Will you  have been working when I arrive?
  • He won't  have been studying long enough to qualify.
  • Next week Jane is going to swim from England to France. By the time she gets to France she'll  have been swimming non-stop for over thirteen hours.
Note that continuous  tenses are also called progressive  tenses. So the Future Perfect Continuous tense is sometimes called the Future Perfect Progressive tense.

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