他教数学教的很好。

He teaches maths well.

youdao

他教数学已很多年了。

He taught mathematics for many years.

youdao

他教数学有点技巧。

He has a knack of teaching mathematics.

youdao

But, you know, I know someone who was a teacher in a Chicago public school for decades and lost his job, teaching math to high school kids, because he is gay.

我认识一个任职于,一所芝加哥公立学校几十年的老教师,被解雇了，他在高中教数学，仅仅是因为他是同性恋。

普林斯顿公开课 - 人性课程节选