So, if somebody pokes you with a stick and you say, "Ouch," because it hurts, the poking and the "Ouch" is an unconditioned stimulus causing an unconditioned response.

如果有人用棍子戳你，你会因为疼而叫出来，戳的动作和你的喊叫“,这就是无条件刺激引起了无条件反射。

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Or maybe during the meal, you are feeling a stomachache

又或者在吃饭的时候，你觉得有点肚子疼。

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My throat hurts and I have a fever.

我的嗓子很疼，还有点发烧。

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