If the glass were kept hot enough, it would flow over the molten tin until the top surface was also flat, horizontal and perfectly parallel to the bottom surface.
如果玻璃保持足够的温度，它就会在熔化的锡中流动，直到顶部表面也变得平整、水平，与底部表面完全平行。
2
On top of that, there is a global property value that generally turns parallel portlet rendering on and off.
而且，还有一个相关的全局属性值，可以全面开启和关闭并行 Portlet 呈现功能。
3
Overcome other dimensional limits (e.g. index number of a top-level element, different number of levels in parallel hierarchies, etc.).