--How much are these books?--You don't have to___.They are freeA.pay them B.pay for them C.cost them D.spend them
问题描述:
--How much are these books?
--You don't have to___.They are free
A.pay them B.pay for them C.cost them D.spend them
答
A
pay to 是固定词组
答
B
答
A. pay them