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

The Mysterious Liquid In Yogurt When you open a container of yogurt, youll often see liquid collected on top. Some people mix it back into the yogurt, and others drain it off. What is it, and where does it come from? To solve the mystery of the liqui

发表于:2018-12-31 / 阅读(34) / 评论(0) 分类 英语听力文摘 English Digest

By Ruth Reader Washington, DC 13 February 2008 There is growing concern around the world over illnesses caused by new antibiotic-resistant bacteria, or so-called superbugs, and the decreasing effectiveness of antibiotics to treat infections. Earlier

发表于:2019-01-07 / 阅读(67) / 评论(0) 分类 VOA常速英语2008年(二月)

But methane is actually odorless, too. 但是甲烷也是无味的。 Well then, what stinks? 那么,什么东西这么臭? The foul smell is usually due to volatile sulfur compounds, such as hydrogen sulfide and methanethiol, or methyl mercaptan

发表于:2019-01-17 / 阅读(60) / 评论(0) 分类 TED演讲教育篇

Flatulence, or passing gas, is a normal daily phenomenon. 胀气,或者放屁,是正常的日常现象。 Most individuals, yes, that includes you, 大多数人,是的,这包括你, will make anywhere from 500-1500 milliliters of gas and ca

发表于:2019-01-17 / 阅读(52) / 评论(0) 分类 TED演讲教育篇