Some tags, of course, will be designed to be nested within others, but nothing is explicitly required to declare a tag as nestable.

当然，有些标记设计成嵌套在其它标记内，但是却不需要任何东西 来将标记显式地声明成是可嵌套的。

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Developers and graphic designers can lay out an application's user interface using drag-and-drop controls and special nestable grids to manage and display complex content.

开发人员和美工设计师可以使用拖-放控件和特定的可嵌套的网格来布局一个应用的用户界面以管理和显示复杂的内容。

youdao

His company, which launched in January 2011 in Brooklyn and Manhattan, rents out stackable, nestable, reusable plastic boxes and drops them off and picks them up.

FORBES: Moving Season: Rent a Box