转换成被动语态1．you should turn off the lights after class．2.we must plant more trees.
问题描述：
转换成被动语态1．you should turn off the lights after class．2.we must plant more trees.
答
被动句The lights should be turned off after class.
More trees must be planted by us.
答
The lights should be turned off after class.
More trees must be planted by us.