20层的高层建筑宜选用( )。
A．框架结构
B．框架一剪力墙结构
C．框架一简体结构
D．钢结构
参考答案：B
John,a friend of mine,who got married only last week,spent $ 3 000 more that he_____________for the wedding. [ ]
A. will plan
B. has planned
C. would plan
D. had planned
视频检索与图像检索的关系是什么？视频镜头切换点的分辨主要依据什么因素？对缓慢的摇镜头如何处理？
