the ball hit the boy____A on the back B in the back C on his back D at his back背部用on这我知道，但为什么是用on the back 而不是on his back
问题描述：
the ball hit the boy____
A on the back B in the back C on his back D at his back
背部用on这我知道，但为什么是用on the back 而不是on his back
答
A hit sb +介词+the +身体部位
答
通过部位是否突起区分on和in
back应该用on
答案为A
答
a
答
D
答
A on the back
表示"打/击"某人某部位的英语习惯表达：
hit/pat sb. in +the + face/stomach/eye/rib
hit/pat sb. on +the + nose/head/back
in 一般指较柔软的部位
on一般指较硬的部位