If you place the focus on a button, not only will you will see the dotted line framing the name of the button, but also a thicker shadow under the button selected. This indicates that if you exit the dialogue box by pressing the Enter key, it is the equivalent of pressing that button itself.
如果把焦点放到一个按钮上，那么在那里不仅会显示虚线边框的矩形，而且这样标记的按钮还会有一个与其他的按钮相比较厚重明显些的阴影。此较明显的阴影有如下含义：如果按下回车键结束该对话框，那么此按下的含义与按下目前有较明显阴影的按钮相同。