long before的用法应注意以下几点:单独使用，相当于一个副词，表示比过去某时早得多的时间，意为“老早”、“很久以前”“早就”等，通常与过去完成时连用。同义句比较:Before long he went to Paris.不久他就去了巴黎。
在句中一般作时间状语，可放在句首和句末，多用在一般将来时和过去式的句子中，意思是:“不久” 。If you say something happens before long， you mean it will happen soon or in the near future.
在这场为真理而战的伟大斗争中，存在已久的教会教条输给了理性主义者和科学家。These galaxies may constitute an answer to the long-standing puzzle of the missing baryonic mass in the universe.
美国有线电视新闻网2月16日文章，原题：“Dragon年快乐”还是“Loong年快乐”？ 每个农历新年，都会对应由12种吉祥动物组成的十二生肖之一。今年是“Dragon（龙）年”，或者更确切地说是“Loong（龙）年”——中国媒体更倾向于用后者代指这种传说中的神兽。
According to a new study cheating really does run in the family， at least as far as men areconcerned.
March became the third month when January and February， which were added to the end of the Roman calendar around 700 BCE， instead became the first and second months around 450 BCE.其实意思八九不离十了，是“形容人极度疯狂或非常愚蠢”的意思。
