How to use the Future Perfect Continuous
(also called the Future Perfect Progressive)1: Just like with the other perfect continuous tenses (and the future perfect simple), we can use the future perfect continuous to say 'how long' for an action that continues up to another point in the future. The second point can be a time or another action. Generally, we need 'for + length of time' and if we use 'when' or 'by the time', we usually use the present simple.
- In April, she will have been teaching for twelve years.
- By the time you arrive, I'll have been cooking for hours!
- I've been working here for 11 months and three weeks. (This is correct, but the time is not an easy number.)
- On Tuesday, I will have been working here for one year. (A much easier number.)
- When I see you, I'll have been studying, so I'll be tired.
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