Зуб на зуб не попадает...
Could you, please, tell me what this expression means? (Preferably in English or Spanish) If you could also provide examples of common uses of this sentence, I will highly appreciate it. Thanks.

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It's an idiom! It means that someone is very cold! :) 
"Я так замёрз! Зуб на зуб не попадает!" - "I am very cold!"

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Temblar de frió. Literalmente, dentellar, los dientes se mueven tanto que los de arriba no corresponden a los de abajo.

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Usually when people are extremely cold, they are shaking and their teeth are chattering. That's why people say "зуб на зуб не попадает" when thay want to express how cold they are.

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when your jaw tremble from cold it makes your teeth move. And one tooth from below can't reach another tooth from above