How fires are started and stopped. You have learned that burning is rapid oxidation which gives off light and heat. In order to start a fire, three conditions are necessary: something to burn; something to support the combustion; and a means of lighting the fuel . Having lived all his life in a home where the furnace is kept burning all winter, the average person seldom thinks of the difficulty of starting a fire.
【大学英语四六级考试阅读提高的练习(17)】相关文章:
最新
2016-10-18
2016-10-11
2016-10-11
2016-10-08
2016-09-30
2016-09-30