服务员可以通过（）来了解客人口味及饮食需求
A、观察客人的言谈举止
B、询问客人的年龄
C、询问客人的职业
D、观察客人的国籍
参考答案：A, D
----- As we know, you won’t go back to the USA since you have established a research center here．But how long _____ in America?
----- For almost 10 years．
A．did you study
B．have you studied
C．were you studying
D．have you been studying
缺铁性贫血的改变顺序是
A．低血清铁一骨髓贮存铁减少一贫血
B．低血清铁-贫血一骨髓贮存铁减少
C．骨髓贮存铁减少一贫血-低血清铁
D．贫血一骨髓贮存铁减少一低血清铁
E．骨髓贮存铁减少一低血清铁一贫血
