Bacteria are extremely small living things. While we measure our own sizes in inches or centimeters, bacterial size is measured in microns. One micron is a thousandth of a millimeter: a pinhead is about a millimeter across. Rod-shaped bacteria are u

发表于:2018-11-28 / 阅读(424) / 评论(0) 分类 新概念优美背诵短文50篇

Bacteria are extremely small living things. While we measure our own sizes in inches or centimeters, bacterial size is measured in microns. One micron is a thousandth of a millimeter: a pinhead is abo

发表于:2018-12-01 / 阅读(141) / 评论(0) 分类 新东方背诵文选

Did you know that there could be more bacteria living in your mouth than there are people on earth? 你知道吗,寄居于你口中的细菌有可能比全世界的人口数还多? Bacteria love our mouths because the livin is easytheres plenty o

发表于:2018-12-28 / 阅读(46) / 评论(0) 分类 初学者听力文摘精选

This is Scientific American's 60-Second Science. I'm Karen Hopkin. This'll just take a minute. If you want to shell a walnut, it helps to have a nutcracker. And if you want to digest seaweed, it helps to have the right enzymes. Now, a study in the jo

发表于:2019-01-08 / 阅读(49) / 评论(0) 分类 Scientific American(四)月

Experts: Let Produce Dry Out to Avoid Bacteria American researchers say farmers should wait one day after a rain storm or watering their fields to harvest fresh fruits and vegetables. They say gathering the crops at least 24 hours after rainfall incr

发表于:2019-01-12 / 阅读(112) / 评论(0) 分类 2015年VOA慢速英语(七)月

48 Bacteria Bacteria are extremely small living things. While we measure our own sizes in inches or centimeters, bacterial size is measured in microns. One micron is a thousandth of a millimeter: a pinhead is about a millimeter across. Rod-shaped bac

发表于:2019-02-17 / 阅读(45) / 评论(0) 分类 双语有声阅读