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The fundamental point in fabricating a chain reacting machine is of course to see to it that each fission produces a certain number of neutrons and some of these neutrons will again produce fission.
你不是通过遵循规则学会走路的。你是通过实践和跌倒学会的。
解释:酸味食物走筋脉,但过量食用会导致小便不畅,说明饮食需适量。