分类：教育/科学-外语学习-英语考试
问题：英翻汉句子18.Nothavingbeendiscovered, 
18.  Not having been discover, many laws of nature do exist.19.  Granting the achievements to be great, we have no reason to be conceited.20.  But for instruments and equipment, the modern marine scientists would be helpless.21.  Measures have been taken to prevent t18.  Not having been discover, many laws of nature do exist.19.  Granting the achievements to be great, we have no reason to be conceited.20.  But for instruments and equipment, the modern marine scientists would be helpless.21.  Measures have been taken to prevent the epidemic from spreading quickly.
回答：18. Not having been discovered, many laws of nature do exist. 
尽管还未被发现，许多自然法则确实存在.

19. Granting the achievements to be great, we have no reason to be conceited.
就是成就再大，我们也没有理由狂妄自大.
 
20. But for instruments and equipment, the modern marine scientists would be helpless.
倘没有仪器设备，现代的海洋科学家也无能为力.

21. Measures have been taken to prevent the epidemic from spreading quickly.
已经采取了防止传染病快速传播的措施.