Graduate tutor Lars Soderlund says non-native English speakers generally have some trouble with English grammar.

VOA: special.2009.04.30

However I've met many grad students with me or students when I was a tutor who express their frustration to me.

,我与许多研究生相处过,或当导师时的学生,学生曾跟我谈及他们的困扰。

哈佛公开课 - 幸福课课程节选

So he had a French tutor who lived with the family for a long time.

他有一个法语家庭教师，住了在他家很久。

耶鲁公开课 - 1945年后的美国小说课程节选