中文2900字，英文2000字

高层建筑的定义很难确定。可以说2-3层的建筑物为底层建筑，而从3-4层地10层或20层的建筑物为中层建筑，高层建筑至少为10层或者更多。
尽管在原理上，高层建筑的竖向和水平构件的设计同低层及多层建筑的设计没什么区别，但使竖向构件的设计成为高层设计有两个控制性的因素：首先，高层建筑需要较大的柱体、墙体和井筒；更重要的是侧向里所产生的倾覆力矩和剪力变形要大的多，必要谨慎设计来保证。

It is difficult to define a high-rise building . One may say that a low-rise building ranges from 1 to 2 stories . A medium-rise building probably ranges between 3 or 4 stories up to 10 or 20 stories or more .
Although the basic principles of vertical and horizontal subsystem design remain the same for low- , medium- , or high-rise buildings , when a building gets high the vertical subsystems become a controlling problem for two reasons . Higher vertical loads will require larger columns , walls , and shafts . But , more significantly , the overturning moment and the shear deflections produced by lateral forces are much larger and must be carefully provided for .