The lever gets them out of the box, but after more and more trials, they stopped scratching at the bars and pushing at the ceiling.

杠杆让它们出了盒子，但在越来越多的尝试之后，它们不再抓栏杆和推天花板。

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When rats are trained to self-administer by pushing a lever, they'll push it over and over again — even hundreds of times — to get a single dose of cocaine.

当老鼠被训练到能够通过推动操作杆来自己施用药物时，它们就会反复不断的推——甚至上百次——来获得一剂量的可卡因。

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Unlock the plunge mechanism by pushing up the plunge lock lever (R). Plunge the router down as far as it will go, allowing the bit to just touch the workpiece.

向上推垂直调节锁定杆（R）松开垂直调节系统，将雕刻机本体向下压到底，使刀头刚好接触到工件表面。

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Pulling this lever or pushing the button would actually rotate the paper enough so that you'd be on a new line and it would also move the little imprinting head that prints the letters of the alphabet and such all the way to the left.

拉杆或按下按钮会让纸翻一下,这样你就能在新的一行上打字了,同时移动打印字母的,压印头,这样也能移到最左边。

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