第一部分 阅读理解 (75分)
Until the twentieth century cigarettes were not an important threat (威胁) to public health. Men used tobacco mainly in the form of cigars (雪茄烟), chewing tobacco, pipe tobacco(烟草), and snuff (鼻烟). Most women did not use tobacco at all.
The cigarette industry began in the 1870s with the development of the cigarette manufacturing machines. This made it possible to produce great numbers of cigarettes very quickly, and it reduced the price.
Today cigarettes smoking is a widespread habit. About forty-three percent of the adult men and thirty-one percent of the adult women in the United States smoke cigarettes regularly. It is encouraging to note, however, that millions of people have given up the smoking habit. Seventy-five percent of the male population and forty-six percent of the these men and eleven percent of the women have stopped smoking. The number of persons who have given up smoking is increasing.
Men as a group smoke more than women. Among both men and women the age group with the highest proportion (比例) of smokers is the age group 24-44.
Income, education, and occupation all play a part in determining a person's smoking habits. City people smoke more than people living on farms. Well-educated men with high incomes are less likely to smoke cigarettes than men with fewer years of schooling and lower incomes. On the other hand if a well-educated man with a high income smokes as all, he is likely to smoke more packs of cigarettes per day.
The situation is somewhat different for women. There are slightly more smokers among women with higher family incomes and higher education than among the lower income and lower educational groups. These more highly educated women tend to smoke more heavily.>>