当男女客人同时到达时，要（）。
A.先问候女宾，再问候男宾
B.先问候男宾，再问候女宾
C.女宾和男宾一起问候
D.女宾和男宾都不问候
参考答案：B
We spent many years studying the formation of rocks, experiencing many sufferings and even dealth .But our hard work _____in the end, and we made it.
A．paid off
B．paid back
C．given away
D．came out
不能在M-H琼脂上生长良好的细菌是
A．肺炎链球菌B．金黄色葡萄球菌C．肺炎克雷伯菌D．大肠埃希菌E．铜绿假单胞菌
