Question

You_____ all those calculations! We have a computer to do that sort of thing.

A．needn’t have done	B．must not have done
C．shouldn’t have done	D．can not have done

Answer 1

A

情态动词用法。A本不需要做某事却做了；不存在B这个结构；C本不应该做某事却做了。D不可能做了某事。句意：你本不需要做所有的计算。我们有计算机做这样的事情。