六级阅读冲刺的训练5

　　Some plants get so hungry they eat flies, spiders, and even small frogs. Whats more amazing is that these plants occur naturally (in special environments) in every state. In fact, theyre found on every continent except Antarctica.

　　Youve probably seen a Venus flytrap. Its often sold in museum gift stores, department stores, and even supermarkets. A small plant, it grows 6 to 8 inches tall in a container. At the end of its stalks(茎)are specially modified leaves that act like traps. Inside each trap is a lining of tiny trigger(触发)hairs. When an insect lands on them, the trap suddenly shut. Over the course of a week or so, the plant feeds on its catch.

　　The Venus flytrap is just one of more than 500 species of meat-eating plants, says Barry Meyers-Rice, the editor of the International Carnivorous Plant Societys Newsletter. Note: Despite any science-fiction stories(科幻小说)you might have read, no meat-eating plant does any danger to humans.

　　Dr. Meyers-Rice says a plant is meat-eating, only if it does all four of the following: attract, kill, digest, and absorb some form of insects , including flies, butterflies, and moths. Meat-eating plants look and act like other green plantswell, most of the time.

　　All green plants make sugar through a process called photosynthesis(光合作用). Plants use the sugar to make food. What makes meat-eating plants different is their bug-catching leaves. They need insects for one reason: nitrogen(氮). Nitrogen is a nutrient that they cant obtain any other way. Why Almost all green plants on our planet get nitrogen from the soilMeat-eating plants cant. They live in places where nutrients are hard or almost impossible to get from the soil because of its acidity(酸度). So theyve come to rely on getting nitrogen from insects and small animals. In fact, nutrient-rich soil is poisonous to meat-eating plants. Never fertilize(施肥)them! But dont worry, either, if they never seem to catch any insects. They can survive, but theyll grow very slowly.

　　Questions 1 to 5 are based on the passage above.

　　According to the passage,carnivorous plants_____.

　　A.only grow in wild filed

　　B.are rare to see

　　C.are as common as flies

　　D.cannot grow on Antarctica

　　2.Venusflytrap preys on insects by_____.

　　A.its numerous elongated stalks

　　B.a container where it grows

　　C.its insect-catching leaves

　　D.the lining of tiny trigger hairs

　　3.We can conclude from the third paragraph that_____.

　　A.carnivorous plants are dangerous

　　B.carnivorous plants are fictional

　　C.carnivorous plants occasionally eat books

　　D.carnivorous plants are harmless to humans

　　4.Carnivorous plants eat insects in order to_____.

　　A.make sugars through photosynthesis

　　B.obtain a nutrient called nitrogen

　　C.make food and nectar

　　D.develop to a more advanced form

　　5.In the eyes of the author,which of the following statements is TRUE?

　　A.Carnivorous plants cannot grow in acid soil.

　　B.Carnivorous plants can grow in nutrient-poor soil.

　　C.Carnivorous plants will die if they cannot catch any insects.

　　D.Carnivorous plants can get nitrogen from nutrient-rich soil

　　D.Carnivorous plants can get nitrogen from nutrient-rich soil