It is important( ) A for us to do eye exercise B for us to do eye exercise C of us to do exercise DB for us to do eye exercises

问题描述:

It is important( ) A for us to do eye exercise B for us to do eye exercise C of us to do exercise D
B for us to do eye exercises

A

A for us to do eye exercises
A和B怎么一样的?exercise要加s

A与B相同,应该有一个是 for us to do eye exercises,正确答案就是 for us to do eye exercises