Section_ⅣLearning_about_Language_&_Using_Language

　　CHEMICAL① OR ORGANIC② FARMING?

　　Over the past half century, using chemical fertilizers③ has become very common in farming. Many farmers welcomed them as a great way to stop crop disease and increase production④. Recently, however, scientists have been finding⑤ that long­term use of these fertilizers can cause damage to the land and, even more dangerous, to people's health.

　　What are some of the problems caused by chemical fertilizers⑥？ First, they damage the land by killing the helpful bacteria⑦ and pests⑧ as well as the harmful ones. Chemicals also stay in the ground and underground water for a long time. This affects crops and, therefore, animals and humans, since chemicals get inside the crops and cannot just be washed off. These chemicals in the food supply build up⑨ in people's bodies over time⑩. Many of these chemicals can lead to⑪ cancer or other illnesses. In addition, fruit, vegetables and other food grown with chemical fertilizers⑫ usually grow too fast to be full of much nutrition⑬. They may look beautiful, but inside there is usually more water than vitamins and minerals⑭.

　　①chemical/'kemIkl/adj.化学的；关于化学的

　　②organic/ɔː'ɡænIk/adj.有机的；器官的；组织的

　　organic farming 有机耕作

　　③fertilizer/'fɜːtIlaIzə/n.肥料；化肥

　　chemical fertilizer 化肥

"over the past＋时间段"常与现在完成时连用；动名词短语using chemical fertilizer