Future progressive tense is used to indicate action which will be taking place at some time in the future.
I will be singing at Symphony Hall next month.
We'll be leaving next Monday.
When you arrive, I'll be cooking dinner.
The future progressive tense is formed by adding will be to the ?ing form of the main verb.
She will be coming around the mountain in a few minutes.
She'll be riding a white horse into town.
The future progressive tense is not as common as other tenses, and it can some-times be replaced by simple future, present progressive or even simple present.
I'll be leaving in a few minutes.
I'll leave in a few minutes.
I'm going to leave in a few minutes.
I'm leaving in a few minutes.
I leave in a few minutes.