将下列句子变成被动语态形式.
问题描述：
将下列句子变成被动语态形式.
1.He hasn't heard from his sister since she left home in 1998.
2.You must turn off the light before you go to bed.
3.People say that they will complete the repair of the old temple by 2012.
4.My aunt gave me a beautiful present on my birthday.
5.The workers were repairing the machine at this time yesterday.
答
1. His sister hasn't been heard from since she left home in 1998.2. THe light must be turned off before you go to bed3. It is said that the repair of the old temple will be completed by 2012.4. I was ...