四川省眉山市2014
高考英语阅读理解、完形填空专题训练（15）附答案 radioactivity is dangerous. it may cause skin burns, it may destory good tissues(组织) and it may cause illness that could be passed on to our children and grandchildren. in case of exposure (暴露) it may even cause death. in the early days of radioactivity, scientists did not realize these dangers. marie and pierre
