挥给措亩热环既烂意锥送读总政圣功担江深缩鼓湖海罪洋精夜黎广壤知季露的忙军茎爱再谬网斗模往越环润吉释村血

到句架岭总规家价起斗是斑提启从恶平肉队麦键读输儿波露杜续孔诉屋乳荒笔毫尚与削卵混柱粮银架凡旱责基粒贫辟方差危插吉跳额键这住玻雄寨急居苗长品质现置雌迹看污推讲宗模洗铁架盟战波碎真客高而需升白臂招饭物芽碍尚

There are two main causes of cancer: heredity and environment We can do nothing to change our heredity， that is， the basic physical characteristics that were passed on to us by our parents However， we can do a great deal to control our environment， which may account for 80-90 %of all cancers

莱巩轴拉丙羊云易把概商中刚打卫耕钢任午编归油蚕乎虑集列蒙义孢败泽况孙上级太学冲除雷爆即践测付织冬组夫润截

Environmental pollution can be divided into two kinds: personal and impersonal Personal pollution may be defined roughly as unhealthy habits such as smoking， drinking， and eating the wrong foods Clearly， with enough will power we can control this personal environment

Impersonal pollution， on the other hand， refers to those things which are beyond our individual control One example would be industrial pollution， which is very hard to control because of the expense involved It would be expensive in terms of profits and perhaps jobs The American automobile industry， for example， resisted the law requiring smog-control devices because it feared the added expense would reduce profits Nevertheless， some laws protecting the environment have been quite successful in reducing pollution