为什么How much are the sweets?的答语是It's 10 yuan a piece.为什么问时是"are they ,后面答就成了"It's"

问题描述:

为什么How much are the sweets?的答语是It's 10 yuan a piece.
为什么问时是"are they ,后面答就成了"It's"

因为前面指的是总价,后面指的是单价