The problem of testing statistical hypotheses is an old one, and its origins are obscure.
检验统计假设的问题由来已久，其起源已不可考。
文化适应不是一个被动的过程，而是一个主动的过程，涉及技术和社会的创新。
过去总是紧张的，未来是完美的。
Laughter and tears are both responses to frustration and exhaustion. I myself prefer to laugh, since there is less cleaning up to do afterward.
生活的意义在于产生影响，而不是赚取收入。