真题考研

The human brain contains 10 thousand million cells and each of these may have a thousand connections. Such enormous numbers used to discourage us and cause us to dismiss the possibility of making a ma...

After the violent earthquake that shook Los Angeles in 1994, earthquake scientists had good news to report: The damage and death toll (死亡人数) could have been much worse.More than 60 people died...

Even plants can run a fever, especially when they’re under attack by insects or disease. But unlike humans, plants can have their temperature taken from 3,000 feet away-straight up. A decade ago...

A good modern newspaper is an extraordinary piece of reading. It is remarkable first for what it contains: the range of news from local crime to international politics, from sport to business to fashi...

A breakthrough (突破) in the provision of energy from the sun for the European Economic Community (EEC) could be brought forward by up to two decades, if a modest increase could be provided in the E...

Just seven years ago, the Jarvik-7 artificial heart was being cheered as the model of human creativeness. The sight of Barney Clark-alive and conscious after trading his diseased heart for a metal-and...

A raped means of long-distance transportation became a necessity for the United States as settlement (新拓居地) spread ever farther westward. The early trains were impractical curiosities, and for...

With fifteen years Britain and other nations should be well on with the building of huge industrial complexes for the recycling of waste. The word rubbish could lose its meaning because everything whi...

By 1970, according to a World Wildlife Fund report, only about 4,500 tigers survived throughout the world-half of them in India. Mr. Foresters, who followed and counted tiger footprints, estimated tha...

In only two decades Asian Americans have become the fastest-growing U.S. minority (少数民族). As their children began moving up through the nation’s schools, it became clear that a new class...