Most of the students felt rather disappointed at the English party. They say that it better organized.
A. had been
B. had to be
C. must have been
D. could have been
网友回答
A. had been
B. had to be
C. must have been
(答案→)D. could have been
解析：考查时态，句意：大部分学生在英语晚会上觉得相当失望。他们说他本来可以组织的更好。“could+have+done”是虚拟语气，表示对过去事情的假设，意思是本来能够做某事而没有做。故选D。