11-year-old和11 years old有什么区别
问题描述：
11-year-old和11 years old有什么区别
答
第一个相当于形容词‘ 11岁的’ 后要接名词
第二个作表语,后不能接名词‘ 11岁’
如
He is an 11-year-old boy.
The boy is 11 years old .