六级翻译冲刺专项训练（25）

　　3. If ever there will be time for environmental health professionals to come to the frontlines and provide leadership to solve environmental problems, that time is now.

　　[参考译文]如果说有需要环保专业人员站出来担负起领导责任的最佳时机的话，现在可谓是正当其时。

　　4. The Times newspaper agrees, complaining that quality has suffered as student numbers soared, with close tutorial supervision giving way to mass production methods more typical of European universities.

　　[参考译文]《泰晤士报》对此有同感，它报怨说，由于学生人数激增，教学质量受影响，因为个别指导不得不让位于欧洲大陆国家高校里惯有的大规模生产方式。

　　5. If food already contains natural carcinogens, it does not make sense to add dozens of new man-made ones.

　　[参考译文]尽管食品中已经含有了天然的致癌物质，但是，再人为地增加一些有毒物质也是很不应该的。

　　6. By studying mineral grains found in material ranging from rocks to clay articles, previous researchers have already been able to identify reversals dating back 170 million years, including the most recent switch 730,000 years ago.

　　[参考译文]通过研究岩石，陶器等一系列材料中含有的矿物颗粒，先前的研究人员已能够确认早在1.7亿年发生的磁场两极转化现象，以及发生在73万年以前的最新一次两极转化现象。

　　7. Several theories link polarity flips to external disasters such as meteor impacts.