mistakes是可数的，mistakes是mistake的复数形式。mistake既可以作名词也可作动词，作为名词意思为错误、过失、失策，作为动词时意思为误会、把…误认为。例句：His costly mistake resulted in severe loss。他的严重的错误导致了重大的损失。

　　例句

　　（1）用作名词(n.)

　　His costly mistake resulted in severe loss.

　　他的严重的错误导致了重大的损失。

　　You've made several grammatical mistakes in the composition.

　　你的作文中犯了几处语法错误。

　　Tom must have taken your dictionary by mistake.

　　汤姆一定是弄错了才拿了你的字典。

　　（2）用作动词(v.)

　　You mistook my meaning entirely.

　　你完全误解了我的意思。

　　I used to mistake his reserve for haughtiness.

　　我过去常把他的沉默寡言误以为高傲。

　　I mistook the number and went to the wrong room.

　　我记错了号码,走错了房间。

　　常用短语

　　in mistake for错当成;

　　make no mistake(about)不犯错误（关于）

　　If I mistake not如果我没弄错的话;

　　mistake about〔in〕(v.+prep.)弄错，看错

　　mistake for(v.+prep.)把…错认为，错把…当作

　　There be no mistaking...弄错，误解；认不出;误会;看错