。此周期从产品的设计开始到人们不再需要它为止。Р Nevertheless, immediately afterwards ,I felt a bit surprised at my rash promise, for, with already too Р many irons in the fire, I could hardly spare any time . Р As one of the highest institutes of learning in the country , peking university has long history of Р revolutionary patriotism as well as an academic tradition of seeking truth from facts all of which is Р praise-worthy. Р 作为全国最高学府的北京大学,我们有悠久的爱国主义的革命传统,有着实事求是的学术传Р 统,这些都是难能可贵的。Р 您好,欢 迎您阅读我的 文章, 本WORD文档可 编辑修 改,也 可以直接打印 。阅读过后, 希望您 提出保 贵的意见或建 议。阅读和学 习是一 种非常 好的习惯,坚 持下去,让我 们共同 进步。