题目内容
Rain forests
Tropical rainforests are the most diverse ecosystem (生态系统) on Earth, and also the oldest. Today, tropical rainforests cover only 6 percent of the Earth's ground surface, but they are home to over half of the planet’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 Earth's axis, the Northern and Southern hemispheres each spend part of the year tilted away from the sun. Since rainforests are at the middle of the globe, located near the equator, they arc not especially affected by this change. They receive nearly the same amount of sunlight, and therefore heat, all year. Consequently, the weather in these regions remains fairly constant.
The consistently wet, warm weather and ample sunlight give plant life everything it needs to thrive. Trees have the resources to grow to tremendous heights, and they live for hundreds, even thousands, of years. These giants, which reach 60 to 150 ft in the air, form. the basic structure of the rainforest. Their top branches spread wide in order to capture maximum sunlight. This creates a thick canopy (树冠) level at the top of the forest, with thinner greenery levels underneath. Some large trees grow so tall that they even tower over the canopy layer.
As you go lower, down into the rainforest, you find less and less greenery. The forest floor is made up of moss, fungi, and decaying plant matter that has fallen from the upper layers. The reason for this decrease in greenery is very simple the overabundance of plants gathering sunlight at the top of the forest blocks most sunlight from reaching the bottom of the forest, making it difficult for robust plants to thrive.
The Forest for the Trees
The ample sunlight and extremely wet climate of many tropical areas encourage the growth of towering trees with wide canopies. This thick top layer of the rainforest dictates the lives of all other plants in the forest. New tree seedlings rarely survive to make it to the top unless some older trees die, creating a "hole" in the canopy. When this happens, all of the seedlings on the ground level compete intensely to reach the sunlight.
Many plant species reach the top of the forest by climbing the tall trees. It is much easier to ascend this way, because the plant doesn'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 understory, 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(养分)they need, which is important since they don't have access to the nutrients in the ground.
Stranglers and Buttresses
Some epiphytes eventually develop into stranglers. They grow long, thick roots that extend down the tree trunk into the ground. As they continue to grow, the roots form. a sort of web structure all around the tree. At the same time, the strangler plant'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.
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If you are alone, go for help before you have completed the most urgent first -aid measures
Task 1
Directions: After reading the following passage, you will find 5 questions or unfinished statements, numbered 36 through 40. For each question or statement there are 4 choices marked A, B, C, and D. You should make the correct choice.
It is the vision (设想) of the Public Transit Police Department to achieve a transit system free from crime and disorder. Transit Police programs are designed to enhance safety, increase riders and preserve the quality of our system's structure.
Transit has its own police force committed to the safety of its customers and drivers, serving seven counties and 85 cities in the region. There are 23 full-time officers, 146 part-time officers and five administrative(行政的) staff, devoted to one thing: public safety.
You've probably seen Transit Police officers patrolling(巡逻) bus routes in cars or on foot. During visits with drivers, Transit Police either ride along or they step on board to greet drivers and passengers. Sometimes officers patrol out of uniform--one could be on your next bus. The fare inspectors on Hiawatha light-rail trains are Transit Police officers.
Every new Public Transit bus has an onboard security camera. Videotapes from these cameras help Transit Police identify and charge criminals.
Downtown patrols built up in early 2002 have improved the quality of life for downtown residents and transit customers. Ten full-time police officers are assigned to the Minneapolis and St. Paul downtown areas, to ensure public security.
Downtown arrests have gone from 490 in April-September 2001 to 941 during the same period in 2002.
The responsibility of the police force of Public Transit is to ______.
听力原文： Cornton Vale is a new prison specially designed for women in Scotland. The 226 prisoners there live in small units of seven rooms. There is a kitchen where they cook their own meals and a lounge with fitted carped and armchairs.
The "wake-up, wake-up" called by loudspeaker at 7 every morning is followed by a music program, which creates the atmosphere of a holiday camp. During the day, most of the prisoners are employed in three workshops, making toys or clothing. Their earning—up to 90 pence a week—can be spent in the prison shop.
The gymnasium, which also acts as a cinema and concert hall, has facilities for table tennis, basketball and dancing.
Prisoners, particularly those with long sentences, are encouraged to be independent and take responsibility for themselves and others. This is in many ways much more demanding than simply serving time. Just as the deputy governor of this prison once said, "We try to preserve the prisoners's self-respect as much as possible, by imagining ourselves in their position" ourselves in their position.' His words explain why this new prison is mn in a unique way.
(33)
Coping With Anxiety and Loneliness
With just a few minutes left before school was to start, my six-year-old, Dustin, was pouting. "I don't want to go," he said. Ever since he'd entered first grade, he hated school. What's going on？ I thought as he trudged out the door. If he hates school this much now, how bad will it be later on？
Every kid occasionally grumbles about school. But five to ten percent of kids dislike it so much that they don't want to attend, says Christopher Kearney, director of the Child School Refusal and Anxiety Disorders Clinic at the University of Nevada, Las Vegas.
If a child seems depressed or anxious about school, fakes illness to stay home, repeatedly winds up in the nurse's or principal's office, or refuses to talk about large chunks of the school day, you should be concerned, say school psychologists Michael Martin and Cynthia Waltman-Greenwood, co-editors of Solve Your Child's School-Related Problems.
Fortunately, you can usually solve the problem —sometimes very easily. In our case, my husband and I visited Dustin's class and noticed that the teacher, fresh out of college, called only on kids who scrambled to sit right under her nose. Dustin, who generally sat near the back, was ignored. We simply told him to move up front. He did, and his enthusiasm returned.
Here are some of the most common reasons kids hate school —and strategies to put them back on the road to success:
Anxiety. One fear that keeps children from enjoying school is separation anxiety. It most frequently occurs during times of family stress or when a child is about to enter a new school.
Unfortunately, parents can feed a child's anxieties by the way they respond. With younger kids, watch how you say good-bye those first few days of school. A firm "Have a great day, and I'll pick you up at 2:30!" is more confidence-inspiring than "Don't worry, I can be them in ten minutes if you need me."
Thomas Ollendick, head of an anxiety-disorders clinic for children and adolescents at Virginia Polytechnic Institute and State University in Blacksburg, Va., treated one boy who was anxious about entering middle school. He worded about everything from getting lost in the new school to getting beaten up. His mother took time off from work so she could stay home to "be there" for him —" inadvertently sending the message that something dreadful might indeed happen," Ollendick recalls.
Once the mother realized she was contributing to the problem, she began fostering her son's independence by taking him to the school so he could learn his way around and meet his homeroom teacher. His fears diminished, and now he's a well-adjusted student.
You can help your child handle fearful situations —from speaking up in class to taking tests —by rehearsing at home. Help make large projects less daunting by breaking them into manageable pieces. Teach your child to replace thoughts such as "I'm going to flunk" with "I can handle this."
Loneliness. Some kids dislike school because they have no friends. This may be the case if your child is always alone, feigns (假装) illness to avoid class outings or gives away treasured possessions in an attempt to be liked.
Often loneliness problems can be solved by bolstering (增强) social skills. "A child may need to learn how to look others in the eye when he speaks, or how to talk above a whisper —or below a yell," Ollendick says. You might teach a young child a few "friendship openers", such as "My name's Tom. What's yours？ Do you want to play tag？"
"A lot of kids who are very lonely have never been told anything good about themselves," says Miami teacher Matty Rodriguez-Walling. "If a lonely kid is skilled
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