Have you ever noticed the colour of the water in a river or stream after a heavy

Have you ever noticed the colour of the water in a river or stream after a heavy

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Have you ever noticed the colour of the water in a river or stream after a heavy rainfall? What do you think caused this change in colour? It is soil that has been washed into the river from the riverbank or from t}le nearby fields.
Components of Soft
Soil is made up of a number of layers(层),each having its own distinctive colour and texture.The upper layer is known as the litter.It acts like a blanket.limiting temperature changes and reducing water loss.The topsoil layer is made up of small particles of rock mixed with rotten plant and animal matter called humus(腐殖质),which is black and gives the topsoil its dark colour.This layer is usually rich in nutrients,oxygen,and water.Below the topsoil is the subsoil,a layer that contains more stones mixed with only small amounts of organic matter.This layer is lighter in colour because of the lack of humus.Beneath the soil lies a layer of bedrock.
Soil forms from the bottom up.Over time bedrock is attacked by rain, wind,frost, and snow.It is gradually broken down into smaller particles in a process called weathering.Plants begin to grow,and rotten materials enrich the topsoil.Most of the soil in Eastern Canada.for example.Was formed from weathered rock that was exposed when the ice disappeared l2.000 years ag0.
Water Beneath the Soil
Surface water collects and flows above the ground in lakes.ponds.and rivers.Once in the soil or rock,it is called groundwater.Gravity pulls groundwater through the soil in a process called percolation(渗透).Eventually the water reaches a layer called the water table.Under this is bedrock through which water cannot percolate.
As water percolates downward,it dissolves organic matter and minerals from the soil and carries them to deeper layers.This causes a serious problem because plants require these nutrients for growth.
Soil pH
Soil can be acidic.neutral.or basic.The pH of the soil is determined by the nature of the rock
from which it was formed.and by the nature of t}le plants that grow and rot in it.
The acidity of rain and snow can lower the pH of the groundwater that enters the soil.By burning fossil fuels such as coal,oil and gasoline,humans have been contributing to higher levels of acidity in many soils.When fossil fuels are burned.gases are released into the air and then fall back to earth as acid rain.Acid soil increases出e problem of carrying nutrients to lower soil levels.As nutrients are removed,soil is less fertile.Plants grow more slowly in acidic soil,and also become easily attacked by diseases.
小题1:The layer of soil that provides necessary nutrients for plant growth is called.
A.1itterB.topsoilC.humusD.subsoil
小题2:According to the text.which of the following is NOT true?
A.Soil forms from weathered rock on the earth surface.
B.The deeper layer of soil is darker in colour than t}le surface soil.
C.Air pollution is partially responsible for acid soil.
D.Groundwater tends to carry away nutrients for plant growth.
小题3:We can infer from the passage that the water table lies      .
A.between the topsoil layer and the subsoil layer
B.in the subsoil layer above bedrock
C.between the subsoil layer and bedrock
D.in the bedrock layer beneath the subsoil
小题4:The underlined word “dissolve” is used to express the idea that organic matter and minerals from soil are         .
A.rushed away into the river
B.cleaned and purified by water
C.destroyed and carried away by water
D.mixed with water and become part of it

答案

小题1:B
小题2:B
小题3:C
小题4:D
解析

小题1:细节理解题The topsoil layer is made up of small particles of rock mixed with rotten plant and animal matter called humus(腐殖质),which is black and gives the topsoil its dark colour。 This layer is usually rich in nutrients,oxygen,and water.
小题2:推理判断题This layer is lighter in colour because of the lack of humus.Beneath the soil lies a layer of bedrock。可以看出答案
小题3:推理判断题Eventually the water reaches a layer called the water table.Under this is bedrock through which water cannot percolate.可以看出答案
小题4:水渗透下来以后,泥土中有机质和其他物质和水按常识是和水混在一起,然后分解。看出答案。
举一反三
Getting your children to study can be a little like getting them to eat their vegetables.
71   Make a study time and have it at the same time every day. This will help your kids to learn to schedule their day and will give them a sense of control over how they spend their time.
Allow them to study in blocks of time, such as for half an hour with a five-minute break in the middle.    72   Ideal (理想的)study times are after dinner or right after school before dinner.
Never allow your children to study in front of the television, as that will encourage passive activity.   73
You’ll also need to help your kids find the right place to study. After you’ve set up a good study time for little learners, set up a good place where they can get those creative juices flowing.
74   Make sure there is a table or a desk and a comfortable chair.
75   This includes helping them out with their homework sometimes and being there for them with the answers to any questions. The input you give your children during study periods will help form a bond and help make studying enjoyable.
A.Pick a place where your children can study properly.
B.Hold them to the schedule they create for themselves.
C.Finally, spend time with your kids when they’re studying.
D.Keep the atmosphere light and offer lots of encouragement, too.
E. Instead, use TV as a treat or a reward when the homework is completed.
F. Try to stop this bad habit by offering some sort of reward.
G. One of the best ways to form good study habits for your kids is to design a schedule that they keep to.
题型:不详难度:| 查看答案
The True Story of Treasure Island
It was always thought that Treasure Island was the product of Robert Louis Stevenson’s imagination.  ___36___,recent research has found the true story of this exciting work.
Stevenson, a Scotsman, had lived    37    for many years in 1881 he returned to Scotland for a    38    . With him were his American wife Fanny and his son    39     .
Each morning Stevenson would take them out for a long    40    over the hills. They had been   41    this for several days before the weather suddenly took a turn for the worse, Kept indoors by the heavy rain. Lloyd felt the days    42    . To keep the boy happy Robert asked the boy to do some   43   .
One morning, the boy came to Robert with a beautiful map of an island. Robert   44   that the boy had drawn a large cross in the middle of   45   . “What’s that?” he asked “That’s the    46   treasure “said the boy Robert suddenly  47   something of an adventure story in the boy’s   48   While the rain was pouring, Robert sat down by the fire to write a story. He would make the   49    a twelve-year-old boy just like Lloyd.  But who would he the pirate(海盗)?
Robert had a good friend named Henley, who walked around with the   50   of a wooden leg. Robert had always wanted to   51   such a man in a story  52   Long John Silver the pirate with a wooden leg, was   53   .
So thanks to a    54   .September in Scotland a friend with a wooden leg and the imagination of a twelve-year-old boy we have one of the greatest   55   stories in the English language.
小题1:
A.HoweverB.ThereforeC.BesidesD.Finally
小题2:
A.aloneB.next doorC.at homeD.abroad
小题3:
A.meetingB.storyC.holidayD.jib
小题4:
A.LloydB.RobertC.HenleyD.John
小题5:
A.talkB.restC.walkD.game
小题6:
A.quietB.dullC.busyD.cold
小题7:
A.attemptingB.missingC.planningD.enjoying
小题8:
A.cleaningB.writingC.drawingD.exercising
小题9:
A.doubtedB.noticedC.decidedD.recognized
小题10:
A.the seaB.the houseC.ScotlandD.the island
小题11:
A.forgottenB.buriedC.discoveredD.unexpected
小题12:
A.sawB.drewC.madeD.learned
小题13:
A.bookB.replyC.pictureD.mind
小题14:
A.starB.heroC.writerD.child
小题15:
A.helpB.problemC.useD.bottom
小题16:
A.praiseB.produceC.includeD.accept
小题17:
A.YetB.AlsoC.ButD.Thus
小题18:
A.readB.bornC.hiredD.written
小题19:
A.rainyB.sunnyC.coolD.windy
小题20:
A.newsB.loveC.real-lifeD.adventure

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Sometimes you’ll hear people say that you can’t love others until you love yourself. Sometimes you’ll hear people say that you can’t expect someone else to love you until you love yourself. Either way, you’ve got to love yourself first and this can be tricky. Sure we all know that we’re the apple of our parents’ eyes, and that our Grandmas think we’re great talents and our Uncle Roberts think that we will go to the Olympics. but sometimes it’s a lot harder to think such nice thoughts about ourselves. If you find that believing in yourself is a challenge. it is time you build a positive self-image and learn to love yourself.
Self-image is your own mind’s picture of yourself. This image includes the way you look, the way you act, the way you talk and the way you think. Interestingly, our self-images are often quite different from the images others hold about US. Unfortunately, most of these images are more negative than they should be. Thus changing the way you think about yourself is the key to changing your self-image and your whole world.
The best way to defeat a passive self-image is to step back and decide to stress your successes. That is, make a list if you need to, but write down all of the great things you do every day. Don’t allow doubts to occur in it.
It very well might be that you are experiencing a negative self-image because you can’t move past one flaw or weakness that you see about yourself. Well, roll up your sleeves and make a change of it as your primary task. If you think you’re silly because you aren’t good at math, find a tutor. If you think you’re weak because you can’t run a mile, get to the track and practice. If you think you’re dull because you don’t wear the latest trends, buy a few new clothes. But remember, just because you think it doesn’t mean it’s true.
The best way to get rid of a negative serf-image is to realize that your image is far from objective, and to actively convince yourself of your positive qualities. Changing the way you think and working on those you need to improve will go a long way towards promoting a positive self-image. When you can pat(拍) yourself on the back, you’ll know you’re well on your way. Good luck!
46. You need to build a positive self-image when you _________.
A. dare to challenge yourself
B. feel it hard to change yourself
C. are unconfident about yourself
D. have a high opinion of yourself
47. According to the passage, our serf-images _________.
A. have positive effects
B. are probably untrue
C. are often changeable
D. have different functions
48. How should you change your serf-image according to the passage?
A. To keep a different image of others.
B. To make your life successful.
C. To understand your own world.
D. To change the way you think.
49. What is the passage mainly about?
A. How to prepare for your success.   
B. How to face challenges in your life.
C. How to build a positive self-image.
D. How to develop your good qualities.
50. Who are the intended readers of the passage?
A. Parents.
B. Adolescents.
C. Educators.
D. People in general.
题型:不详难度:| 查看答案
We experience different forms of the Sun’s energy every day. We can see its light and feel its warmth. The Sun is the major source of evaporation (蒸发) of water from the oceans and lakes. Sunlight also provides the energy used by green plants to make their own food. These green plants then provide food for all organisms (生物) on the Earth.
Much of the energy that comes from the Sun never reaches the Earth’s surface. It is either reflected or absorbed by the gases in the upper atmosphere. Of the energy that reaches the lower atmosphere, 30% is reflected by clouds or the Earth’s surface. The remaining 70% warms the surface of the planet, causes water to evaporate, and provides energy for the water cycle and weather. Only a tiny part, approximately 0.023%, is actually used by green plants to produce food.
Many gases found in the atmosphere actually reflect heat energy escaping from the Earth’s surface back to the Earth. These gases act like the glass of a greenhouse in that they allow energy from the Sun to enter but prevent energy from leaving. They are therefore called greenhouse gases.
When sunlight strikes an object, some of the energy is absorbed and some is reflected. The amount reflected depends on the surface. For example, you’ve probably noticed how bright snow is when sunlight falls on it. Snow reflects most of the energy from the Sun, so it contributes to the low temperatures of winter. Dark-coloured surfaces, such as dark soil or forest, absorb more energy and help warm the surrounding air.
59. According to the passage, the root cause for weather changes on the Earth is ______.
A. the atmosphere surrounding the Earth                         
B. water from oceans and lakes
C. energy from the Sun                   
D. greenhouse gases in the sky
60. Only a small part of the Sun’s energy reaches the Earth’s surface because most of it _______________.
A. absorbed by the clouds in the lower atmosphere
B. reflected by the gases in the upper atmosphere
C. lost in the upper and lower atmosphere
D. used to evaporate water from the oceans and lakes
61. We learn from the passage that _______________.
A. all living things on the Earth depend on the Sun for their food
B. a forest looks dark in winter because it absorbs solar energy
C. only 0.023% of the energy from the Sun is made use of on the Earth
D. greenhouse gases allow heat energy to escape from the Earth’s surface
题型:不详难度:| 查看答案
What time is it? Most people are pretty accurate in their answer. And if you don’t know for sure, it’s a very likely that you can find out. There may be a watch on your wrist, there may be a clock on the wall, desk, or computer screen; or maybe you’re riding in a car that has a clock in the dashboard (仪表板).
Even if you don’t have a timepiece of some sort nearby, your body keeps its own beat. Humans have an internal clock that regulates (调节) the beating of our heart, the pace of our breathing, the discharge (排出) of chemicals within our bloodstream, and many other bodily functions.
Time is something from which we can’t escape. Even if we ignore it, it’s still going by, ticking away, second by second, minute by minute, hour by hour. So the main issue in using your time well is, “Who’s in charge?” We can allow time to slip by and let it be our enemy. Or we can take control of it and make it our ally.
By taking control of how you spend your time, you’ll increase your chances of becoming a more successful student. Perhaps more importantly, the better you are at managing the time you devote to your studies, the more time you’ll have to spend on your outside interests.
The aim of time management is not to schedule every moment so we become slaves of a timetable that governs every waking moment of the day. Instead, the aim is to make informed choices as to how we use our time. Rather than letting the day go by, largely without our awareness, what we are going to discuss next can make us better able to control time for our own purposes.
小题1:The underlined word “ally” in Para. 3 more likely means somebody or something that is _________.
A.your slave and serves you
B.your supporter and helps you
C.under your control and obeys you
D.under your influence and follows you
小题2:The author intends to tell us that time _____________.
A.could be regulated by a timepiece such as a clock or a watch
B.could be managed by the internal clock of human bodies
C.should be well managed for our own interest
D.should be saved for outside interests
小题3: In the next part, the author would most probably discuss with you ________.
A.how to keep up with the timesB.how to make up for lost time
C.how to have a good timeD.how to make good use of time

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