---John looks a bit upset.Did you tell him the bad news?
---Yes，but I________him after his birthday partyA.should have told B.must have toldC.shouldn’t have told D.needn’t have told
网友回答
A解析这题考查情态动词的完成式的用法：should have told“本应该做却没做”must have done“过去一定做了”，shouldn’t have told“本不应该做却做了”needn’t have told“本不必做某事却做了”，句意是：--约翰看上去有点不安，你告诉他坏消息了吗？--是的，但我不该在他生日的时候告诉他。选A。