Student or Learner
You can use both of / neither of / either of + us/you/them:
· (talking to two people) Can either of you speaking Spanish?
Both / both of......neither / neither of......either / either of !!!!Shouldn't the above question be constructed"Can either of you speak Spanish?"?
But, if this is something you heard, it may have been a rather rare but acceptable usage:
"Can either of you speak in Spanish?"