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If you're not failing every now and again, it's a sign you're not doing anything very innovative.

Every mathematical problem is a puzzle waiting to be solved, and every solution is a step towards greater understanding.

愛是能力和意愿，讓你關心的人成為他們自己選擇的樣子，而不堅持他們必須滿足你。

可持續發展不再是可選項，而是我們對后代的責任。