不对吧，过去发生就用一般过去时，现在发生就用一般现在时啊！我的理解就是这个，下面资料参考参考
各种时态的被动语态举例（以动词do为例）
1．一般现在时（am/ is/ are +done）
English is spoken by lots of people in the world. 世界上的许多人都说英语。
Class meeting is held every Thursday. 每周四都举行班会。
The classroom is cleaned by the students every day. 学生们每天都打扫教室。
2．一般过去时(was/ were +done)
The cup was broken by the boy. 杯子被那个男孩打碎了。
He was saved at last. 他最终获救了。
My bike was stolen. 我的自行车被偷了。
3．一般将来时与过去将来时(will/ shall be +done; would/should be +done)
A speech will be given this afternoon. 今天下午有一个演讲。
A new road will be built next year. 明年要修一条新马路。
I thought thousands of people would be helped. 我认为将有数千人得到帮助。
4．现在进行时与过去进行时(am/ is/ are being +done; was/ were being +done)
The machine was being repaired at this time yesterday. 昨天这时，机器正在被修理。
The problem is being discussed now. 问题正在被讨论。
A bus is being pushed by the passengers. 路人正在推一辆公共汽车。
5．现在完成时(have/ has been + done)
Two hundred trees have been planted by now. 到现在为止，已经种了二百棵树了。
The book has been read many times by me. 这本书已经被我读了许多遍了。
Several soldiers have already been killed in the conflict. 在冲突中已经有几名士兵被杀害。
6．过去完成时(had been+done)
They said they had been invited to the party. 他们说已经被邀请参加晚会了。
She found the house had been destroyed by the storm. 她发现房子已经被暴风雨摧毁。
He had been tortured by the illness for many years before he died.
他在去世前已经被疾病折磨很多年了。
参考资料：http://zhidao.baidu.com/question/17859170.html?si=5