在回答顾客问题时需把握（）原则。
A.适度
B.适时
C.适地
D.合适
参考答案：A
计算：1997+1996+1004+1006+1994+1003=______．
_____ many people here on vacation [ ]
A. They're
B. There are
C. There is
D. There be
