2017年6月英语四级写作练习：塑料袋的危害

四级作文作为拉分的重点部分，应引起同学们足够的重视，小编找了许多作文范文来给同学们练习和提升语感。 Directions: Write a composition entitled Limiting the Use of Disposable Plastic Bags. You should write

US Supreme Court Rules Same-Sex Marriage Is Legal in 2015

The Supreme Court often looks at a major social issue over a series of cases. In the late 1990s and early 2000s, it considered the rights of gay people. At the time, voters in many states had approved laws strongly limiting gay rights. For example, p

经济学人:分子生物学 蛋白质的奥秘(3)

One common protein-contact prediction is that, if the side chain of one member of a pair of amino acids brought close together by folding is long, 一种比较普通的蛋白质接触预测就是，如果一对氨基酸的一个侧链折叠后很长，

经济学人:分子生物学 蛋白质的奥秘(2)

One of the leading researchers in the field of protein folding is David Baker of the University of Washington, in Seattle. 西雅图华盛顿大学的David Baker是蛋白质折叠领域研究者的领军人物之一。 For the past 20 years he and hi

Earth and Sky:Acid Rain 酸雨

Acid Rain 酸雨 Damage from acid rain is widespread - not just in eastern North America, but throughout Europe, Japan, China, and Southeast Asia. Is the rain that's falling on your umbrella acidic? A listener's question -- on today's Earth and Sky. J

美丽英文12

Beliefs 信念 Your beliefs are very powerful and have the power to create or to destroy your life. In most cases, whatever you believe, is what you will become. If you believe that you are loser, that you never get a break in life, that you cant acco

VOA慢速英语--研究人员通过转基因来增加玉米营养

Researchers Genetically Modify Corn to Increase Nutrition Researchers in the United States say they have discovered how to genetically engineer corn to produce a kind of amino acid usually found in meat. The result is a food with increased nutrition

SSS 2010-06-28

This is Scientific American's 60-Second Science, I'm Cynthia Graber. This will just take a minute. Even if you have a light hand with the salt shaker, you probably get lots of sodium in processed or restaurant meals. But sodium can contribute to high

SSS 2009-01-23

This is Scientific American's 60-Second Science. I'm Karen Hopkin. This will just take a minute. As Valentines day approaches, remember, its the thought that counts. Just ask a decorated cricket. Because according to a study published in the January

SSS 2009-04-28

This is Scientific Americans 60-Second Science. Im Karen Hopkin. This will just take a minute. Many of the key molecules for life have a specific direction, or handedness: DNA twists to the right, amino acids to the left. Now scientists at the Nation

知性英语－Acid rain 酸雨

How does acid deposition affect human health? We eat food, drink water, and breathe air that has come in contact with acid deposition. Canadian and U.S. studies indicate that there is a link between t

Designer Antibiotics

85 新功效的抗生素在加州诞生 DATE=8-15-01 TITLE=SCIENCE REPORT - Designer Antibiotics BYLINE=Jerilyn Watson （Start at 1'04

专业术语—口腔生理学术语A2(英文详解)

Ameloblasts- cells which differentiate from ectoderm and secrete enamel during tooth development. Amino acids - building blocks of proteins containing a carboxyl group (COOH) and an amino group(NH2) b

专业术语—基因专业词汇A/B

Egyptians debate over draft law limiting protests

CAIRO, Jan. 5 (Xinhua) -- The draft law limiting protests in Egypt, which is currently being studied after recently being announced by Justice Minister Ahmed Mekki, stirred up an overwhelming debate in the Egyptian political arena. Contradictory repo

VOA常速英语2007年-Acid Attacks Are a Growing Form of Revenge in U

By Birungi Machrine Kampala 26 November 2007 Attacks using acid are becoming more frequent in Uganda. Up to 2003, there were only 145 recorded attacks, but over the last three years, there have already been 87. Survivors often suffer from severe emot

经济学人152:攻破屏障

Science and technology 科学技术 Creutzfeldt-Jakob disease 克雅氏病 Breaking down the barrier 攻破屏障 A glimmer of hope for a drug that treats disease caused by prions 药物治疗朊病毒感染疾病的一线希望 THE epidemic of mad-c

经济学人107:克雅氏病 攻破屏障

Science and Technology Creutzfeldt-Jakob disease Breaking down the barrier 科技 克雅氏病 攻破屏障 A glimmer of hope for a drug that treats disease caused by prions 药物治疗朊病毒感染疾病的一线希望 THE epidemic of mad-cow dis

英语美文："安分"的大象

A number of years ago, I had the rather unique experience of being backstage in Madison Square Garden, in New York, during the Ringling Brothers Barnum Bailey Circus. To say the least, it was a fascinating experience. I was able to walk around lookin

每天吃鲑鱼 像戒烟一样有益

Eating a small steak every day could be as good for you as stopping smoking, scientists say. 科学家说，每天吃一小块牛排可以像戒烟一样对你有好处。 People who eat lots of protein-rich food were found to have lower blood pressu