【正文】 r the passage quickly and answer the questions on Answer Sheet 1.For questions 14, markY (for YES) if the statement agrees with the information given in the passage。 if the statement contradicts the information given in the passage。RainforestsTropical rainforests are the most diverse ecosystem(生態(tài)系統(tǒng))on Earth, and also the oldest. Today, tropical rainforests cover only 6 percent of the Earth39。s plant and animal species.What Is a Rainforest?Generally speaking, a rainforest is an environment that receives high rainfall and is dominated by tall trees. A wide range of ecosystems fall into this category, of course. But most of the time when people talk about rainforests, they mean the tropical rainforests located near the equator.These forests receive between 160 and 400 inches of rain per year. The total annual rainfall is spread pretty evenly throughout the year, and the temperature rarely dips below 60 degrees Fahrenheit.This steady climate is due to the position of rainforests on the globe. Because of the orientation of the Earth39。t have to form its own supporting structure.Some plant species, called epiphytes, grow directly on the surface of the giant trees. These plants, which include a variety of orchids and ferns, make up much of the under story, the layer of the rainforest right below the canopy. Epiphytes are close enough to the top to receive adequate light, and the runoff from the canopy layer provides all the water and nutrients (養(yǎng)分) they need, which is important since they don39。s branches extend upward, spreading out into the canopy. Eventually, the strangler may block so much light from above, and absorb such a high percentage of nutrients from the ground below, that the host tree dies.Competition over nutrients is almost as intense as petition for light. The excessive rainfall rapidly dissolves nutrients in the soil, making it relatively infertile except at the top layers. For this reason, rainforest tree roots grow outward to cover a wider area, rather than downward to lower levels. This makes rainforest trees somewhat unstable, since they don39。 seeds, dropping them some distance away. This helps to disperse the population of the plant species over a larger area.The numerous birds of the rainforest also play a major part in seed dispersal. When they eat fruit from a plant, the seeds pass through their digestive system. By the time they excrete (排泄) the seeds, the birds may have flown many miles away from the fruitbearing tree.There are also a large number of reptiles and mammals in the rainforest. Since the weather is so hot and humid during the day, most rainforest mammals are active only at night, dusk or dawn. The many rainforest bat species are especially well adapted for this lifestyle. Using their sonar, bats navigate easily through the mass of trees in the rainforest, feeding on insects and fruit.While most rainforest species spend their lives in the trees, there is also a lot of life on the forest floor. Great apes, wild pigs, big cats and even elephants can all be found in rainforests. There are a number of people who live in the rainforests, as well. These tribes which, up until recently, numbered in the thousands are being forced out of the rainforests at an alarming rate because of deforestation.DeforestationIn the past hundred years, humans have begun destroying rainforests at an alarming rate. Today, roughly acres of rainforest are destroyed every second. People are cutting down the rainforests in pursuit of three major resources： Lumber for paper and other wood products s rainforests are an extremely valuable natural resource, to be sure, but not for their lumber or their land. They are the main cradle of life on Earth, and they hold millions of unique life forms that we have yet to discover. Destroying the rainforests is parable to destroying an unknown planetwe have no idea what we39。s tropical rainforests will be wiped out within 40 years.1. Virtually all plant and animal species on Earth can be found in tropical rainforests.2. There is not much change in the weather in the tropical rainforests all the year round.3. The largest number of rainforests in the world are located on the African continent.4. Below the canopy level of a tropical rainforest grows an overabundance of plants.5. New tree seedlings will not survive to reach the canopy level unless ________.6. Epiphytes, which form much of the under story of the rainforest, get all their water and nutrients from ________.7. Stranglers are so called because they ________ by blocking the sunlight and peting for the nutrients.8. Since rainforest bacteria and trees depend on each other for life, the relationship they form is termed ________.9. Plant species are dispersed over a large area with the help of ________.10. As we are still ignorant of millions of unique life forms in the rainforest, deforestation can be pared to the destruction of ________.t going to change her major. C) She studies in the same school as her brother.t going to work in her brother39。 B) She prefers a life of continued exploration. D) She doesn39。 B) Talk the drug user out of the habit. D) Keep his distance from drug addicts.14. A) The son. B) The father. D) Aunt Louise.15. A) Stay away for a couple of weeks. C) Look after the Johnsons39。 B) Check the locks every two weeks.t want to warm up for the game.t want to be held up in traffic. D) He wanted to catch as many game birds as possible.17. A) It will reduce government revenues. C) It will mainly benefit the wealthy. dividends.18. A) The man should phone she hotel for directions. C) She doesn39。s phone number.Questions 19 t