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- Jurassic From approx. 185 to 140 million years before present; lower (Lias), middle (Dogger), upper (Malm). 侏罗纪从接近一亿八千五百万到一亿四千万年以前；早侏罗纪，中侏罗纪，晚侏罗纪。
- The Last Glacial Maximum (LGM) is about 21000 calendar years before present, with climate conditions significantly different from the present. 摘要末次冰期冰盛期（或称为末次盛冰期），为第四纪更新世最后一个冰期的鼎盛时期，该时期的气候与当代气候迥然不同。
- Abstract The Last Glacial Maximum (LGM) is about 21000 calendar years before present, with climate conditions significantly different from the present. 摘要末次冰期冰盛期（或称为末次盛冰期），为第四纪更新世最后一个冰期的鼎盛时期，该时期的气候与当代气候迥然不同。
- Demography analyses showed that the Chinese wild boar population had declined since 3300 years before present and expanded recently. 种群动态研究表明，中国大陆野猪种群在距今3300年左右开始下降，而近期种群开始扩张。
- The abrupt precipice cliffs alongside the Jumahe are composed of chert-bedded dolomites which were formed on the sea bottom 1200 million years before present. 拒马河畔的陡崖绝壁是由距今12亿年前在海底生成的燧石条带白云岩构成。
- It may be many years before we meet again. 大概要过许多年我们才能再见。
- The year before the present year. 去年当年之前的一年
- Mary went with Jim for two years before they were married. 玛丽和吉姆恋爱了两年以后才结婚。
- The tiny seeds planted ten years before had flowered. 10年前撒的种子这时已经开花了。
- It so happened/chanced that I'd met her a few years before. 碰巧我几年前见过她。
- They were cohabiting for three years before their marriage. 他们同居了三年才结婚。
- It took several years before he achieved the presidency. 他用好几年才攀上了总裁职位。
- Some of the old plays we had seen years before are revived on the stage. 我们多年前看过的旧戏中有几出重又上演了。
- I was in harness at the factory for over twenty years before it shut down. 我在那家工厂关闭前在那儿工作了20多年了。
- Dick paid court to her at least two years before she agreed to marry him. 迪克追求她至少达两年之久，她才同意和他结婚。
- I bummed around (in) Europe for a year before university. 我在欧洲漫游了一年才上大学。
- A child's education shall begins at least one hundred years before he was born. 儿童教育，应该在还未出生的一百年前开始。
- The England of the last few years before world war I went beyond recall. 第一次世界大战前最後几年中的那个英国社会是再也无法挽回了。
- Always unwrap flowers before presenting them. 3）献花之前不要包扎。
- He bootlegged for years before anyone noticed. 在人们注意之前他已贩酒多年了。
