he was told that a mistake had been made.不太明白a mistake为什么放前面

问题描述:

he was told that a mistake had been made.不太明白a mistake为什么放前面

用来强调这个错误(mistake)

这是(宾语从句)被动语态,所以要提前。看看下面的比较就明白了:
he was told that (he)had made a mistake 。主动语态
he was told that a mistake had been made (by him)被动语态

这是被动式,意思是一个错误被犯了;改成主动形式就是sb had made a mistake.这句话的意思是说,他被告知犯了一个错误.
被动式的作用是强调动作的对象,即被做的事情或者东西,而不强调做动作的人.在这个句子中,由于he已经在前面说明了,所以不需要特别指出这个错误是他犯的;相反,这个句子要强调的是“错误”,而不是“他”,故把a mistake放前面.

那你觉得应该放在那里呢?
一个句子必须有主谓宾吧,不能把主谓宾颠倒啊,除非有一些倒装句。
a mistake 是主语