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In mathematics, the art of proposing a question must be held of higher value than solving it.
在数学中,提出问题的艺术必须比解决问题更有价值。
Happiness is not something ready-made. It comes from your own actions.
儿童的一切教育都必须遵循一个原则,即帮助孩子身心自然的发展。