—George _ you sing so loudly at such a late hour? —I am terribly sorryA. willB. mayC. mu

问题补充：

—George, _ you sing so loudly at such a late hour?

—I am terribly sorry．

A. will

B. may

C. must

D. shall

答案：

A. will

B. may

(答案→)C. must

D. shall

解析：考查情态动词：A．will愿意，会，B．may可以，C．must 必须，偏要，D．shall该，句意是：乔治，你偏要这么晚那么大声的唱歌吗？--我很抱歉。选C。