Question

--- Have you told him we have changed the plan?I _____ have, but I haven’t done it yet. A．mu.

--- Have you told him we have changed the plan?I _____ have, but I haven’t done it yet. A．must B．ought to C．needn’t D．can’t

Answer 1

B

试题分析：考察情态动词用法。A必须，一定；B应该；C不必；D不可能；ought to have done本应该做某事，实际上却做未。Must have done一定做了某事；needn’t have done本不需要做某事，实际上却做了。句意：—你告诉他我们改变计划了吗？—我本应该告诉他，但是我还没有告诉他呢。根据句意说明B正确。 点评：本题是高考必考考点，一定要牢记句型意思。must have done过去肯定做了某事。should have done 本应该做而实际未做。can’t have done 过去不可能做了某事；shouldn’t have done 本不应该做而实际做了。 need have done 本有必要做某事；needn’t have done 本没有必要做某事；注意没有 mustn’t have done的形式。