比如这个

来源: 于 2019-01-22 11:57:17 [旧帖] [给我悄悄话] 本文已被阅读：次

but behind their back she thinks they are crazy coming to this place, yes, she believes most of the students are just wasting time, she believes they wont improve

你怎么证明这个是事实呢？