听力课堂英语四级频道为各位备考四级的同学们，整理了大学英语四级听力美文第81篇:Salaries，希望对大家有所帮助，一起来看一下吧！

　　英语四级听力美文第81篇:Salaries

　　Economists and experts on wages have long tried to discover what factors were influencingpeople's salaries.

　　Most of the factors they listed one or two centuries ago are still important today.

　　One of those is education: college graduates have earned and are still earning more thanworkers who have only finished high school, and high-school graduates earn more than workerswho didn't complete their studies there.

　　The difficulty and length of preparation for a profession also plays a part in the size of thesalary.

　　Danger and responsibility make a difference too - the man or woman in charge of a project, theperson performing a difficult or dangerous task, the airplane pilot responsible for many humanlives, usually get a proper compensation for their pains.

　　And yet there are exceptions to those rules.

　　Due to the needs of modern industry, technicians with no college education are nowcommanding high salaries, much closer to the college graduates'salaries than they used to be inthe past.

　　And there are many jobs in which danger doesn't bring much compensation.

　　Why doesn't a fireman earn more than a postal clerk, for example?

　　And what about the policeman and the coal miner, who risk their lives for a modest salary?

　　The answer is simple.

　　Actually, salaries are governed by a combination of factors, the most important being oneknown as the law of supply and demand, which says that the value of goods and services isdetermined by the quantity available compared with the number of possible buyers.

　　If there are more chickens on the market than people wishing to buy them, the price of poultrygoes down.

　　If the number of specialized engineers is much larger than the number of positions open tothem, the salaries drop even for the most impressive applicants.