Question About Progressive Tenses

[afashoro]

I know from the guide that progressive tenses are "Used to emphasize ongoing nature of an action. Use verb "to be" and the present participle (-Ing form)." For example:
-Present Progressive - Sandy IS PLAYING soccer.
-Past Progressive - Sandy WAS PLAYNG soccer yesterday.
-Future Progressive - Sandy WILL BE PLAYING soccer tomorrow.

However, I also read "Do not use to indicate future actions. This usage is considered too colloquial. Instead, use simple future". Given this advice, what's the purpose of future progressive and when would one use it?

[tim]

The purpose of the future progressive is exactly what you said: indicating ongoing action. I think it is typically avoided because we don’t know for certain how long a future activity will be ongoing. However, it would definitely be acceptable and appropriate to say "Sandy will be playing soccer from 9 to 5 tomorrow"..