秘书在安排完（）的工作后，就应着手制作商务旅程表。
A．订房订票
B．物品携带
C．日常事务
D．差旅费用
参考答案：A
My friend me. I have to leave now. [ ]
A. waits for
B. waited for
C. is waiting for
D. was waiting for
简述玉米杂交种亲本种子的繁殖与提纯技术。
