It's how you can initialize a variable to like zero for counting's sake or something like that.

你可以初始化一个变量，像0用来,计数的或者诸如此类的。

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It goes out to the outside world, interacts,gets its hand and mind dirty, does work outside and then applies its work and learns from "the dirty experiences" and brings it back to the lab and so on and so on in an upward spiral.

而是走到外面的世界，与外界互动，接触那些“肮脏“事物，在外面工作，并吸取经验,从“肮脏经验“中学习“,将得到的经验带回实验室,诸如此类，就像一个上升的螺旋。

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