标签：话题作文 话题 英语四级作文
字数：1500字
提要：本文由 为您整理Throuthout history man has changed his physicai environment in order to improve his way of life.With the tools of technology he has altered many physical feathures of the earth.He has transtormed woodlands and prairies into farms and made lakes and reservoirs out of rivers for irrigation purposes or hydroelectric power.Man has also modified the face of the earth by draining marshes ..