----You look pale and upset.
----Yes, my girl friend an online chat with me non-stop until six o’clock this morning.
A. have been having
B. had had
C. was having
D. am having
网友回答
A. have been having
B. had had
(答案→)C. was having
D. am having
解析：until six o’clock this morning是一个过去的时间状语, 故用过去进行时表示过去持续的动作。注意A项的干扰作用。