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.
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.
河南清理“上访训诫中心”
延迟退休?人们更倾向于“退休返聘”
上海出新规整治“群租”
644批次“儿童用品”抽检不合格
“中央一号文件”锁定“三农”主题
玉兔“故障”
小升初将严控“特长生”招生
失联飞机或采用“地形掩护”技术
奥巴马发布“国情咨文”
杭州暂停“活禽贸易”和“信鸽放飞”
河北保定“政治副中心”说被否认
人民币兑美元“汇率波幅”扩大
飞北京航班“盲降”
“电子鞭炮”点燃环保风
政协建议将“体育考试”纳入高考
李娜澳网夺冠
东莞扫黄重打“保护伞”
春晚升级为“国家项目”
闲话“中山装”
今年流行“半成品年夜饭”
构建中美“新型大国关系”
科学家承认“汽车尾气”是雾霾元凶
“索契冬奥会”开幕
马年新春“微信红包”满天飞
米歇尔“访华”
中国经济增长的“四维模式”
反腐重拳向“会所”出击
“转基因奶牛”将入市
俄呼吁冲突各方“奥林匹克休战”
养老金将实行“城乡并轨”
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