"What would you guys like to do this afternoon?"
I'm pretty sure that the subject can be used to start the phrase, ie:
i had the same question, but just asked chinese wife. she says it has to be 今天下午. said people dont really say 这个下午
im done with this crap. ive been learning chinese for years and its really annoying that for some word orders you take the sentence wrong. things like that are messing with my placement test. for god's sake
The order should be flexible. But given that this is beta, they probably just haven't been able to account for every variation for every answer yet.