每年在长江中下游地区常出现的天气现象有[ ]
A．梅雨和伏旱
B．寒潮和台风
C．沙尘暴和寒潮
D．沙尘暴和大雾
答案：A
A接口的物理层基于（）Mbit/s的PCM链路
A.1
B.1.5
C.2
D.2.5
E.3
Jane’s pale face suggested that she _______ill, and her parents suggested that she ________medical examination.
A．be; should have
B．was; have
C．should be; have
D．was; has
