---You realize that you were driving at 100 miles per hour,don't you?---No,officer,I ________ have been．This car can't do more than 70．A.needn'tB.couldn'tC.shouldn'tD.might not
网友回答
B解析考查情态动词，have been后省略了driving at 100 miles per our．情态动词couldn't — have done表示不可能做了某事。