对于未饱和空气而言，当温度一定时露点温度越低表明空气（）
A.越容易凝结
B.越不容易凝结
C.相对湿度越大
D.绝对湿度越大
参考答案：B
–My sister hasn’t received any reply from the company yet, so she wants to give up.
-- My advice is that she _____ till next week.
A．has been waiting
B．waits
C．wait
D．will wait
什么叫倍频器？
