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.
趣味英语绕口令:一座漂亮的房子
小学英语绕口令 让你“发晕”的趣味句子
少儿英语绕口令:雪白的天鹅
小学英语绕口令 梦想中的梦想
趣味英语绕口令 戴桂冠的小丑
英语绕口令 一只伶俐的野鸡
趣味英语绕口令 Purple Paper People
小学英语 英语绕口令 (54条)
儿童英语绕口令 贝蒂布特买黄油
趣味英语绕口令
儿童英语绕口令 明亮的夜灯
儿童英语绕口令 雾蒙蒙,冰霜冻
小学英语绕口令系列二
趣味英语绕口令 字母H
小学英语绕口令集锦:S
用你最有个性的方式来说英语绕口令
少儿英语绕口令 吹笛子难
英语绕口令:贝蒂布特的黄油
趣味英语绕口令:渔网有裂口
英语绕口令:我们的桨是橡树吗?
儿童英语绕口令 请准时缴款
英语绕口令C
小学英语 英语绕口令
儿童英语绕口令 All Al's sly allies lie
少儿英语绕口令:渔网有裂口
小学英语绕口令 我有一种想法
趣味英语绕口令:10只母鸡与10支钢笔
小学英语绕口令集锦:J-N
小学英语绕口令集锦A
小学英语绕口令及译文1
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