矿井通风的任务就是为了排除井下的有害气体。
参考答案：错
- Is James at home?
-- No, he Ya'an to be a volunteer.
A. has gone to B. has been to C. is going to
哪些行为可能导致投诉产生。（）
A.回答顾客问题
B.开门营业的时候
C.节假日
D.歧视顾客
