Study this example situation:
These people are standing in line to get into the stadium.
an hour from now
An hour from now, the stadium will be full.
Everyone will be watching the game.
three hours from now
Three hours from now, the stadium will be empty.
The game will have ended.
Everyone will have gone home.
I will be doing something (future continuous) = I will be in the middle of doing it:
I’m leaving on vacation this Saturday. This time next week, I’ll be lying on the beach or swimming in the ocean.
You have no chance of getting the job. You’ll be wasting your time if you apply for it.
Compare will be doing and will do:
Don’t call me between 7 and 8. We’ll be having dinner.
Let’s wait for Maria to arrive, and then we’ll have dinner.
Compare will be doing with other continuous forms:
At 10:00 yesterday, Kelly was at the office. She was working. (past)
It’s 10:00 now. She is at the office. She is working. (present)
At 10:00 tomorrow, she will be at the office. She will be working (future)
We also use will be -ing to talk about complete actions in the future.
The government will be working a statement about the crisis later today.
Will you be going away this morning?
Later in the program, I’ll be talking to the Minister of Education …
Our best player is injured and won’t be playing in the game on Saturday.
In these samples, will be -ing is similar to (be) going to …
We use will have done (future perfect) to say that something will already be complete before a time in the future.
Sally always leaves for work at 8:30 in the morning. She won’t be at home at 9:00 – she’ll have gone to work.
We’re late. The movie will already have started by the time we get to the theater.
Compare will have done with other perfect forms:
Ted and Amy have been married for 24 years. (present perfect)
Next year they will have been married for 25 years. (future perfect)
When their first child was born, they had been married for three years. (past perfect)