单词：
单词： 相关文章
Severe drought has sent river levels in parts of central and northern China to record lows, affecting millions of hectares of farmland and leaving more than a million people short of water。 严重干旱已导致华中和华北部分地区河水水位
英文语法词汇
图片 by Jason Marshall Some math is functional. Some math is fun. And some math is simply stunning. If that last description sounds improbable to you, then today just might change your mind. Because now that weve covered enough ground, were going t
数学英语
This is Scientific American's 60-Second Science. I'm John Matson. Got a minute? Earth's surface is dominated by oceans. But where did all that water come from? Asteroids and comets smashing into the early Earth have long been thought to be a promisin
Scientific American(十)月
Study: No Evidence Hydraulic Fracturing Pollutes Water A new study finds no evidence that the controversial practice to extract natural gas known as hydraulic fracturing is contaminating ground water. The report, Separating Fact from Fiction in Shale
VOA标准英语2012年(二月)
Fact: liquid water is heavier than air. Fact: clouds, which consist of water droplets and ice crystals, seem to hover in the air. One final fact: the water droplets in a typical cloud together weigh many tons. Which raises a question: how do clouds s
英语时差8，16
BEIJING, May 13 (Xinhuanet) - China's central bank announced on Saturday it would lower the reserve requirement for commercial lenders by 50 basis points, the second time it has taken such action this year to inject more market liquidity and shore up
英语新闻