这个英语句子有没有语法错误
问题描述：
这个英语句子有没有语法错误
They think surfing the internet is hamful to not only our health but also our studing so that we aren't supposed to surfing the internet often but in correct time.
答
有三处
studing可改成 study,study可以直接做名词；
so that 意思是“目的是”,应改成so "所以"
be supposed to后跟动词原形,因此,后一个surfing应改成 surf