单选题 "You realize that you were driving at 100mph, don't you?" "No, officer, I {{U}}may not{{/U}} have been. This car can't do more than 80."
【正确答案】 D
【答案解析】[分析] 情态动词应用 在此因表过去不大可能发生的事，应用couldn't+have+过去分词；因此D为答案。