基本结构：will/ shall + be + 动词过去分词。
e.g. He will announce a great news at the meeting this afternoon.（主动）
A great news will be announced by him at the meeting this afternoon.（被动）
被动语态的结构：
1.一般现在时:am/is/are done
You are required to do this.
2.一般过去时：was/were done
The story was told by her.
3.一般将来时：shall/will be done
The problem will be discussed tomorrow.
4.一般过去将来时：should/would be done
He said that the trees would be planted soon.
5.现在进行时：is/am/are being done
The question is being discussed in the meeting room.
6.过去进行时：was/were being done
The new road was being made.
7.现在完成时：has/have been done
The novel has been read.
8.过去完成时：had been done
He said that the work had been finished.
