Passive voice
1. If the subject of active voice sentence is "you", do we need to say "by you" in passive voice?
For example: "You shouldn't replace the roof." - "The roof shouldn't be replaced by you."
2. Is the position of "already" in this passive voice sentence correct: "The TV have already been mended."?
Thank you very much! ^^

Question

Passive voice
1. If the subject of active voice sentence is "you", do we need to say "by you" in passive voice?
For example: "You shouldn't replace the roof." -> "The roof shouldn't be replaced by you."
2. Is the position of "already" in this passive voice sentence correct: "The TV have already been mended."?
Thank you very much! ^^

Answer

1. Yes. 
2. Yes, although it would be more common to say, "The TV has already been fixed."