He without saying good-bye to them, for he always has good manners.
A. mustn’t have left
B. may not leave
C. shouldn’t have left
D. can’t have left
网友回答
A. mustn’t have left
B. may not leave
C. shouldn’t have left
(答案→)D. can’t have left
解析：解本题一定要注意审题，要把题目看完整，才不会想当然选C，根据后文的for he always has good manners可以断定“他不可能不打招呼就离开”，用can’t have left.