广播消息的非“倒金字塔”结构，又可细分为（）
A.引导结构
B.时序结构
C.逻辑结构
D.耗散结构
E.双线结构
参考答案：A, B, C
Miss Green didn't talk much to other people. There was always_________ a little sad about her. [ ]
A. everything
B. anything
C. nothing
D. something
钢梁、钢塔架、人行道栏杆支架等都应进行保护涂装，防止钢结构生锈。
