抑郁发作时，一日之内的规律是（）
A.昼轻夜重
B.昼重夜轻
C.中午起逐渐加重
D.中午最严重以后减轻
E.半夜最重
参考答案：B
Would you please keep silent? The weather report ______ and I want to listen to it.
A．is broadcast
B．has been broadcast
C．is being broadcast
D．had been broadcast
用瀑布模型开发软件有哪两个前提？
