Venus and Earth Compared Venus, the second planet from the Sun, lies, on average, 108 million km from the Sun, about 30% closer than the Earth. Venus is often referred to as our sister planet because of similarities in size, mass, density a... 详情>>
2018-12-24
Science fiction is a genre of fiction in which at least part of the narrative depends on the impact of science, either real or imagined, to generate settings or events which have not yet occurred in reality (and may never do so). Robert A.... 详情>>
2018-12-20
Science fiction is a genre of fiction in which at least part of the narrative depends on the impact of science, either real or imagined, to generate settings or events which have not yet occurred in reality (and may never do so). Robert A.... 详情>>
2018-12-20
Missions to Mars: a rocky road to the Red Planet Missions to Mars may have stalled, but the search for signs of life continues – by analysing the DNA of Martian meteorites, writes Roger Highfield. Are we alone in the cosmos? For centuries... 详情>>
2018-12-20
ROBOTS are getting smarter and more agile all the time. They disarm bombs, fly combat missions, put together complicated machines, even play football. Why, then, one might ask, are they nowhere to be seen, beyond war zones, factories and te... 详情>>
2018-12-20
1. 表转折： but， however， yet， in fact， on the other hand； A， but B： 否定A而肯定B，则A，B两部分内容是相反的。 例如：Computerized data storage and electronic mail were to have heralded the paper less of... 详情>>
2018-12-20
单词是阅读的基础，没有一定量的单词作为基础，就无法保证有一定的阅读速度。那么学习一些最基本的构词法知识，就非常重要了。 虽然不是每一个单词都可以通过构词法解决掉，但... 详情>>
2018-12-20
雅思阅读提高方向，当然是词汇。 任何一篇内容相对复杂的阅读文章，都不可避免地出现大量生僻词语或者是难度相对较大的单词。从文章的选材而言，范围是十分丰 富的，主要来自... 详情>>
2018-12-17
In the earliest stages of mans development he had no more need of money than animals have. He was content with very simple forms of shelter, made his own rough tools and weapons and could provide food and clothing for himself and his family... 详情>>
2018-12-17
Background music may seem harmless, but it can have a powerful effect on those who hear it. Recorded background music first found its way into factories, shop and restaurants in the US. But it soon spread to other arts of the world. Now it... 详情>>
2018-12-17
