The land surface pokes just a couple of meters on average above sea level, making it the lowest-lying nation in the world.

VOA: standard.2009.10.17

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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You go to the dentist and he pokes you.

你去看牙医，他捅你。

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