问题补充：
---You’re late! You were to be here an hour ago.
--- Sorry, Mr. Hu.
A. sorry
B. surprised
C. supposed
D. happy
答案：
A. sorry
B. surprised
(答案→)C. supposed
D. happy
解析：sorry遗憾的，抱歉的；surprised吃惊的；supposed假定的；happy高兴的。句意：你迟到了，你应该一小时前到达这里的。Be supposed to do sth应该做某事，被期望做某事，故选C。
