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不要擔(dān)心你在數(shù)學(xué)上遇到的困難；我敢保證我遇到的困難比你還大得多。

And when your stomach is empty and your mind is full,it's always hard to sleep.

The measure of intelligence is the ability to change.

SILENCE. Speak not but what may benefit others or yourself; avoid trifling conversation.

To sequence DNA is to read the book of life.