He developed the theory of classical conditioning by making a distinction between two sorts of conditioning, two sorts of stimulus response relationships.

他通过区分两种条件作用,两种刺激反应关系，提出了经典条件作用理论。

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Through the simple tools of classical conditioning then, the shoe becomes a conditioned stimulus giving rise to the conditioned response of sexual pleasure.

接下来，通过经典条件作用，鞋子变成了条件刺激,引起了性快感这一条件反应。

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Well, when Pavlov, for instance, started before conditioning there was simply an unconditioned stimulus, the food in the mouth, and an unconditioned response, saliva.

比如，在条件作用形成之前,只是简单的存在着无条件刺激，即食物，以及无条件反应，即唾液。

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