When do we use the future perfect continuous tense in English?
Note: This is also called the future perfect progressive tense.
As a general rule, we use the future perfect continuous to talk about actions that will continue up to or finish just before a point in the future.
❗We do not usually use stative verbs (know, like, own, etc.) in the future perfect continuous.
For example:
- In December, we will have known him for six months. (Not:
we will have been knowing) - By next year, I’ll have owned this car for ten years. (Not:
I’ll have been owning)
We use the future perfect continuous for:
1. Actions that continue up to a specific future time
We often use the future perfect continuous to emphasise the duration of an activity (“how long”) in progress at a specific future time.
For example:
- In July, I will have been living here for ten years.*
- By 10 pm, she’ll have been studying for 8 hours.
- In one week, they won’t have been playing tennis for a year. They only started ten months ago.
- On Monday, how long will we have been teaching English for?
*Imagine it is the middle of June.
You can say:
– I have been living here for nine years, eleven months and two weeks.
You could also say:
– I have been living here for almost ten years.
But if you want to be precise and use a simple number, you can say:
– In July, I will have been living here for ten years.
We can use the future perfect simple in all of the examples above and the meaning does not significantly change.
Compare:
- In July, I will have been living here for ten years.
- In July, I will have lived here for ten years.
Here the difference in meaning is small. With the future perfect simple, the focus is on the completion or achievement. The future perfect continuous highlights the ongoing or continuous nature of the action.
Note: In both cases, the action might continue beyond that point.
2. Actions that continue up to another future action
We can also use it to show the duration of a continuous activity that happens right before another future action. Depending on the context, the activity might continue after that point.
Here we often use when or by the time in the other clause.
For example:
- When you get home, I’ll have been cooking for two hours.
(Event 1: I cook for two hours. Event 2: You get home.) - By the time the students sit their exam, they will have been preparing for months.
- When she arrives, he won’t have been waiting for an hour.
- How long will you have been working by the time you take your break?
Note: As for rule 1, we can technically use the future perfect simple here as well, but the future perfect continuous sounds more natural when the action is continuous in nature.
3. Actions that finish just before a future point
We can use the future perfect continuous for actions that finish shortly before a future time or another future action. We often use it to explain why something will be true or noticeable.
For example:
- I’ll have been cleaning the house when you come over, so I’ll be quite dirty.
- She’ll be tired by 7 pm because she’ll have been working all day.
- The ground will be wet because it will have been watering the gardens.
4. Predictions about the duration of an activity up to a future point
For example:
- By midnight, she probably will have been driving for twelve hours.
- By 2050, scientists will have been researching the problem for decades.
- I think they will have already been playing for a couple of hours by the time we arrive.