761.They _____ have arrived at lunchtime but their flight was delayed.
A.will
B.can
C.must
D.should
762.If you _______ smoke,please go outside.
A.can
B.should
C.must
D.may
761.答案是D;考查虚拟语气用法。should have done本应做某事，而实际没做。
762.答案是C;考查情态动词用法。此处must偏偏，偏要，表示与说话人的愿望相反或不耐烦。
