-My son are five years old,and I want to buy him some books,please.-OK.These books are _____kids.-My son are five years old,and I want to buy him some books,please.-OK.These books are _____kids.用适当的介词填空,补全句子
问题描述：
-My son are five years old,and I want to buy him some books,please.-OK.These books are _____kids.
-My son are five years old,and I want to buy him some books,please.
-OK.These books are _____kids.
用适当的介词填空,补全句子
答