：几个句子改为被动语态 1.You may answer the question by yourself an hou

1.The answer may be answered by yourself in an hour.
2.The new school will be visit by them tomorrow.
3.He was seen to play the piano at home by me.
4.A new bridge had been built by us in WanZhou.
(你第4句的now打错了吧,应该是new)