被动语态
1) The blackboard and chalk _______________(正在被电脑和投影机所取代).
2) The book _______________(到今年年底就将已出版).
3) Computer models _______________(可以用来演示细胞工作的方式).
4) When the bill of fare was brought, _______________(我惊呆了，价格大大超出了我的预料).
5) _______________(必须立即采取有效措施)to eliminate sandy storms.
1) is being replaced by the computer and the projector
2) will have been published by the end of this year
3) can be used to demonstrate the way that cells work
4) I was startled, for the prices were a great deal higher than I had anticipated
5) Effective measures must be taken immediately
