Put up your ______if you know the answer, please.

问题描述:

Put up your ______if you know the answer, please.

hands

hand

hand/hands

hands
举手

hands
hand可数名词,前面没有a
put up hands
但这里有your,your hand可以代表你的一个手,所以这里用hand也可以
put up your hand
所以这里hand/hands都可以