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谚语, 成语 and 歇后语

To pull a tooth from a tiger’s mouth.
虎口拔牙 (Hǔ kǒu bá yá)

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A fox borrows the tiger’s might.
狐假虎威 (Hǔ jiǎ hǔ wēi)

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Deadly as she can be, a tigress will never eat her own cubs.
虎毒不食子 (Hǔ dú bù shí zǐ)