某些事件和其他处理程序不同，比如单击一个超链接，会引发称为默认动作的活动。

Distinct from any handler, some events, such as clicking on a hyperlink, can cause activity called a default action.

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因为每一次我们加入一个交际圈，增加一条超链接或者交另一个朋友，这项活动就立刻通过News Feed被其他的朋友看到，每一个facebook的行为是对我们不知名的观众的独白。

And because every time we join a network, post a link or make another friend it's immediately made visible to others via the News Feed, every Facebook act is a soliloquy to our anonymous audience.

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