He has been followed, day by day,year by year, by a strange luck.

VOA: special.2010.03.27

by luck or by inside information or by something, while there's sort of a big academic debate.

单纯的用运气或者内幕消息或者其他东西来解释，尽管对此学术界也存在着极大的争论。

耶鲁公开课 - 金融市场课程节选

The romance heroine is often threatened with rape, but by her cleverness or by good luck or a concatenation of forces ; she can always invariably avert that tragedy; and by the end of the work she can present herself to her future husband as a virgin.

这位传奇的女英雄总是被强奸所威胁，但是多亏了她的机敏，或是走好运，或是一连串的军队暴力,她总是能避免悲剧;,在作品的最终,她呈现在未来丈夫面前的仍是一个处女。

耶鲁公开课 - 弥尔顿课程节选

So far attacks in the U.S. - at least those that are publicly known -- have been thwarted by heightened security awareness and increased counterterrorism measures from the U.S.side, as well as by both bad luck and professional incompetence on the terrorists' part.

VOA: standard.2010.05.05