natural oftenness 自然频率
high oftenness knotter 高频除节机
fractional oftenness precession 分频进动
The caprice of nature, the unexpectedness of diseases and the oftenness of wars could cut a person's life short in his prime or in his infancy (more often the cases).
反复无常的自然、突如其来的疾病以及无休无止的战争都会让一个人的生命在壮年甚至婴儿时期（这种情况更是频繁）就戛然而止。 此句英文非常地道，值得学习。
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