Amy better last night, but she was a little nervous and didn’t reach her best standard.A. could perf

【题目】Amy ______ better last night, but she was a little nervous and didn’t reach her best standard.

A. could perform B. must have performed

C. should perform D. could have performed

【答案】D

【解析】

试题分析：考查虚拟语气。含蓄条件句, but表转折，表示与过去事实相反，主句使用“情态动词+have done”。must have done表示对过去的肯定推测，could have done表示在过去本能做某事。句意：艾米昨晚本能表演的更好，但她有点紧张，未能发挥她最好的水平。故选D。