O-4：on the side 另外

A:What does your friend Jim do?
A：你的朋友吉姆是干什么的？

B:He is a teacher, but he makes a little money on the side by repairing cars in his free time.
B：他是个教师，但也在空闲时兼修汽车赚点钱。

A:He can repair cars? I can't believe it.
A:他会修汽车？真没看出来。

B:Believe me, he is the first-class.
B：相信我，他修车技术是一流的。