Depending on the state of the program, a mouse down might start drawing a line, or it might select an object.

根据程序的状态，鼠标按下事件，应该开始绘制一条直线，或者选中一个对象。

youdao

For example, are selections done on mouse-down or mouse-up events?

比如，是在mouse - down还是在mouse - up事件发生时才算完成选择？

youdao

What else can you detect as a yes or no answer is the mouse down?

当鼠标点下时，除了检查真假还能检测什么？

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Scientists have created a mouse with Down Syndrome, and claim it has already revealed unknown features of the human version of the disorder.

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The REX is also designed to offer Windows 8 users more routine tasks, such as mouse pointing and scrolling down pages.

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Look for the enemies to start up a power blow and block it to get a chance for a nasty retaliatory strike, and charge up your own power attacks by holding down the mouse button.

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