g.I always hear him play the piano at night.(变被动语态)He heard his sister crying just now.(变被动语态)
问题描述：
g.I always hear him play the piano at night.(变被动语态)
He heard his sister crying just now.(变被动语态)
答
1 He is always heard by me to play the piano at night .
2 His sister was heard by him crying just now .