Most animals have little connection with animals of a different kind, unless they hunt them for food. Sometimes, however, two kinds of animals come together in a partnership(伙伴关系) which does good to both of them. You may have noticed some birds sitting on the back of sheep. This is not because they want a ride, but because they find easy food in the parasites(寄生虫）on sheep. The sheep allow the birds to do so because they remove the cause of discomfort. So although they can manage without each other, they do better together.Sometimes an animal has a plant partner. The relationship develops until the two partners cannot do without each other. This is so in the corals(珊瑚）of the sea. In their skins they have tiny plants which act as “dustman”, taking some of the waste products from the coral and giving in return oxygen which the animal needs to breathe. If the plants are killed, or are even prevented from light so that they cannot live normally, the corals will die.小题1:Some birds like to sit on a sheep because _________. A．they can eat its parasites B．they consider the sheep as their shelter C．they enjoy traveling with the sheep D．they find the position most comfortable 小题2:The underlined word “they” in the first paragraph refers to _______. A．birds and parasites B．sheep, birds and parasites C．parasites and sheep D．birds and sheep 小题3:It can be learnt from the text that the coral depends on the plants for ________. A．comfort B．light C．oxygen D．food 小题4:What does the second paragraph mainly discuss? A．Some plants depend on each other for food. B．Some animals and plants develop their relationship easily. C．Some animals and plants depend on each other for existence. D．Some animals live better together.
| 小题1:A 小题2:D 小题3:C 小题4:C |
| 试题分析：文章介绍自然界中有的动物和动物之间看相处的很好，还有的植物和动物是互相依存的关系。 小题1:细节理解题。答案即在“This is not because they want a ride, but because they find easy food in the parasites (寄生虫) on sheep.”一句之中。可知鸟喜欢坐在羊的身上，是想吃羊身上的寄生虫，选A 小题2:猜词题：前文中的“The sheep let the  birds do so because they can stop the parasites from troubling them.”的意思是说“绵羊让鸟儿落在自己身上，因为鸟儿可以将它们身上的寄生虫吃掉。”；另一句“So though they can do with it by themselves…”的意思是说“尽管它们自己也能对付寄生虫……”。综合上面两句话的意思，再结合“…they can do better together with each other.”这一句话，可知they指的是鸟和羊，即得答案为D小题3:细节题：根据第二段的句子：“…taking the useless things from the coral and giving oxygen in return. That is what the animal needs to live.”这两句话可知，珊瑚需要植物提供的氧气才能生存下去。选C 小题4:推理题：根据第二自然段的内容，Sometimes an animal has a plant partner.珊瑚和它们体内的植物具有相互依存的关系。C |
