一般多、高层建筑主要有几种类型？
参考答案：五种竖向体系：混合结构体系、框架结构体系、框—剪结构体系、剪力墙结构体系、筒体结构体系。
We have been told that under no circumstances _______ the telephone in the office for personal affairs. [ ]
A. may we use
B.we may use
C. we could use
D. did we use
失血性休克时如何补充血容量。
