被动语态改写英语句子This song is heard ( )now.A singing B to sing C sa

This song is heard ( )now.
A singing
现在听到这首歌正在被唱.
The students in Class 4 didn't sweep the floor last Friday.
改：the floor wasn't swept last friday by the students in class 4.
Did he take an umbrella just now?
改:Was an umbrella taken by him just now?
Did that factory make TV sets in 1999?
改:Was Tv sets made by that factory in 1999?