We can begin our discussion of “population as global issue” with what most persons mean when they discuss “the population problem”: too many people on earth and a too rapid increase in the num
Plastics are materials which are softened by heat and set into lasting form when shaped in a mold. Some are natural; some are semi-synthetic(半合成的) , the result of chemical action on natural su
The difference between a liquid and a gas is obvious under the conditions of temperature and pressure commonly found at the surface of the Earth. A liquid can be kept in an open container and fill it
Here’s to Your HealthAs the only freshman on his school’s varsity(代表队) wrestling team, Tod was anxious to fit in with his older teammates. One night after a match, he was offered a whisky bo
Since its foundation in 1954, the United Nations has written into its major covenants(契约) the need to establish minimum ages for marriage. But the custom of marriage is a highly sensitive cultural
As you all know, the United States is a country on wheels. Nearly eight million new cars are made each year; four households out of five own at least one car, and more than a quarter have two each. Ye
2016年12月大学英语六级阅读试题库整理汇总12016年12月英语六级考试阅读试题库整理一22016年12月英语六级考试阅读试题库整理二32016年12月英语六级考试
The striving of countries in Central Europe to enter the European Union may offer an unprecedented chance to the continent’s Gypsies (or Roman) to be recognized as a nation, albeit one without a def
Why the inductive and mathematical sciences, after their first rapid development at the culmination of Greek civilization, advanced so slowly for two thousand years—and why in the following two hund
In the last two hundred years there have been great changes in the method of production of goods. This is now also true of the building industry; for mechanization has been introduced. System building