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材料的重量決定了形式。

Persistence is key in mathematical research; many great results come from looking at the same problem from different angles over and over again.

孩子越能夠?qū)Ｐ?，就越能從工作中得到平靜，就越能發(fā)自內(nèi)心地紀(jì)律或規(guī)則。