we know that the exhibition is arranged today at first,but it has been put off until next week.

题目

we know that the exhibition is arranged today at first,but it has been put off until next week.
we know that the exhibition is（这里可以用was吗?） arranged today（定在今天,这样翻译可以吗?） at first,but it has been（如果前面用was,这里就用had been吗?但是推迟是后发生的） put off until next week.

答案

可以用was,但是用了was,再用had been,就错了!
用了was,还是用has been就行.
正因为“put off”发生在“arranged”后,所以才不可以用过去完成时.
其实,过去完成时一点也不复杂,你只要记住一个总原则：过去完成时是表示“过去的过去”,就任何问题也难不倒了.
比如这个句子,很明显,arranged是“过去”,而“put off”并不是在“arranged”之前,所以就不是“过去的过去”,不可以用过去完成时.
举个类似的例子：The exhibition had been arranged today at first,but it was put off in the end.
最初的时候,展览被安排在今天,后来,它又被取消了.
在这个句子里,put off 是“过去”,而arranged发生在put off之前,所以是“过去的过去”,所以就要用过去完成时.