误：Five people were killed in the car incident.

正：Five people were killed in the car accident.

析：incident 主要指普通的小事件, 也可指暴力性的政治事件；而 accident 则指偶然的不幸事件(即指事故)。

◆他做这事是偶然的, 还是故意的?

误：Did he do it on accident or by purpose?

正：Did he do it by accident or on purpose?

析：by accident 是习语，表示“偶然地”；on purpose 也是习 语，表示“故意地”，注意两者介词的搭配不能混淆。