27. Scientific Theories In science, a theory is a reasonable explanation of observed events that are related. A theory often involves an imaginary model that helps scientists picture the way an observed event could be produced. A good example of thi

发表于:2018-12-08 / 阅读(349) / 评论(0) 分类 新概念优美背诵短文50篇

Lesson 10Allow 1.Please allow me to tell you the truth . 2.My father doesn't allow me to smoke . 3.Please allow me to do experiments in this laboratory . 4.I don't allow him to use my computer . 5.Passengers are not allowed to smoke . 6.My brother wo

发表于:2018-12-16 / 阅读(77) / 评论(0) 分类 辛沛沛NO-BOOK 辛沛沛口语初级版

When they hear the name Ben Franklin, many folks think of the Declaration of Independence, the Continental Congress and things like that. Not as many people remember that Franklin was an inventor . . . and a good one, too! He also did some pioneering

发表于:2018-12-28 / 阅读(57) / 评论(0) 分类 初学者听力文摘精选

The most powerful atom smasher ever built could make some bizarre discoveries, such as new forces of nature or even extra dimensions of space, after it's switched on in August. The Large Hadron Collider, or LHC, basically consists of a ring of super

发表于:2018-12-30 / 阅读(154) / 评论(0) 分类 国家地理2008年

This is AP News Minute. Republican Senator Cindy Hyde-Smith won Mississippi Senate election run-off. She defeated Democrat Mike Espy and becomes the first women elected to Congress from Mississippi. The Chinese scientist who claimed to have help make

发表于:2019-01-04 / 阅读(169) / 评论(0) 分类 美联社新闻一分钟2018(十一)月

分集介绍:本节课所讲为振动与波。教授对电磁场的有关计算给出了详尽的说明和推导过程,并用生动的实验和图片解释光波的偏振现象,告诉我们为什么天空是蓝色的,为什么日出和日落是

发表于:2019-01-05 / 阅读(71) / 评论(0) 分类 麻省理工学院公开课:振动与波

Dutch Experiment Shows Farming With Salty Water Possible 荷兰实验表明盐水种植农作物成为可能 One of the many adverse effects of global climate change is the rise of sea levels, which scientists say can increase the salinity level of f

发表于:2019-01-14 / 阅读(67) / 评论(0) 分类 VOA标准英语2014年(十一月)

A World Health Organization panel of medical ethicists has ruled it is ethical to offer unproven drugs or vaccines to people infected or at risk of infection in West Africa's deadly Ebola outbreak. Meanwhile, one of three Chinese medical teams sent t

发表于:2019-01-18 / 阅读(88) / 评论(0) 分类 2014CRI中国国际广播电台

13.Usuallythefirsttospotdatathatwereinconsistentwithotherfindings,inthisparticularexperimentsheletanumberof_______resultsslipby. A.inaccurate B.verifiable C.redundant D.salient E.anomalous KEY:E 翻译

发表于:2019-02-01 / 阅读(76) / 评论(0) 分类 英文语法词汇

One of the world's foremost analysts of North Korea's ballistic missile programs says reports of missile engine testing at a newly revealed facility appear credible. North Korea is apparently able to test its missiles under more realistic conditions

发表于:2019-02-14 / 阅读(86) / 评论(0) 分类 VOA双语新闻 2008年9月

When I was six years old, my first grade teacher had this brilliant idea. She wanted us to experience receiving gifts but also learning the virtue of complimenting each other. And she said, Why don't we just stand here and compliment each other? If y

发表于:2019-03-04 / 阅读(119) / 评论(0) 分类 英语PK台