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I'm not afraid of risks, I'm afraid of regrets.

The more I write, the more I disappear.

To teach mathematics is to inspire the next generation of thinkers and problem solvers.

No one had ever had such a friend, so affectionate,so loyal and so skillful.

采礦業必須在不影響效率的情況下發展以滿足可持續發展的需求。