--- I paid him 300 yuan for the sneakers．
--- Oh, he charged you too much．You them with half the money．
A. could have bought
B. needn’t have bought
C. must have bought
D. wouldn’t have bought
网友回答
(答案→)A. could have bought
B. needn’t have bought
C. must have bought
D. wouldn’t have bought
解析：考察虚拟语气.句意:我付给他300元买这双运动鞋.——哦，他跟你要价太高了。你完全可以以半价买这双鞋。表示对过去的虚拟用could have done，故选A。