I should have remembered this was a "future" lesson, but I didn't and I got it wrong, because this is badly pronounced. When you stress "be", you're saying "beberam" and that is the Past Perfect. If you mean the future "beberão", you must stress "ão".
I'm just wondering, how common is it to say "beberão" in comparison to "Vão beber"?
I'm a native English speaker and never thought there was a difference, but apparently there is. http://www.ehow.com/info_8737159_use-thing-vs-something.html