如果客户需要快速得到调研结果，下列调研方式不适合的是（）。
A.街上拦截访问
B.电话访问
C.邮寄访问
D.因特网
参考答案：C
— I rang the bell for a long time last night, but no one opened the door.
— Oh, the family __________ a party and they didn’t hear the bell.
A．had
B．were having
C．had had
D．have had
外感咳嗽的病因是
A．六淫B．七情C．外伤D．劳倦E．饮食
