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You have to be willing to fail, to be wrong, to start over again with lessons learned.

I have made a ceaseless effort not to ridicule， not to bewail， not to scorn human actions， but to understand them.

A mathematician's work is never done; there are always new questions to explore and new mysteries to uncover.

"A good picture book is a silent conversation between the artist and the child."

我不放棄，我升級。