在砖混结构中的墙体承重体系，大体分为三钟，( )不属于其中。
A．混合承重体系
B．纵向承重体系
C．横向承重体系
D．内框架承重体系
参考答案：A
If the dog hadn't woken us, we wouldn't have noticed the fire and it _____ to the house next door. [ ]
A. could spread
B. should have spread
C. would spread
D. might have spread
船板性能的基本要求是具有一定的（）。
A、强韧性
B、成型性
C、焊接性能
D、耐磨性
