After the heavy mudslide happened in Sichuan, hundreds of newspaper reporters were sent to ____ the natural disaster.
A. describe B. cover C. witness D. experience
高三英语单项填空中等难度题
After the heavy mudslide happened in Sichuan, hundreds of newspaper reporters were sent to ____ the natural disaster.
A. describe B. cover C. witness D. experience
高三英语单项填空中等难度题查看答案及解析
After the 3 – day trap in the mudslide in Zhouqu(舟曲), the old man ________in the end.
A．passed down B．passed by C．passed on D．passed away
高三英语单项填空简单题查看答案及解析
After the 3 – day trap in the mudslide in Zhouqu(舟曲), the old man ________in the end.
A．passed down B．passed by C．passed on D．passed away
高三英语单项填空中等难度题查看答案及解析
Usually there might be a lot of accidents in the heavy fog. I happened to witness _______ this morning.
A. it B. those
C. one D. that
高三英语单项填空中等难度题查看答案及解析
(2013·临沂市一模)Usually there might be a lot of accidents in the heavy fog.I happened to witness ________ this morning.
A．it B．those
C．each D．one
高三英语单项填空中等难度题查看答案及解析
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．
1.The layer of soil that provides necessary nutrients for plant growth is called．
A．1itter B．topsoil C．humus D．subsoil
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．
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
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
高三英语阅读理解困难题查看答案及解析
After 1953 _______ people have succeeded in climbing the mountain.
A. several hundred of B. several hundreds C. several hundreds of D. several hundred
高三英语单项填空中等难度题查看答案及解析
. Recently a terrible earthquake happened in Sichuan, ____the people are still suffering.
| A．from their effects | B．of which effects |
| C．of its effects | D．from whose effects |
高三英语单项填空简单题查看答案及解析
It happens from time to time that after a whole morning of studying, you are tired in the afternoon. It’s then that you might want to eat something sweet, perhaps a Coke or a chocolate bar, to lift your mood. After all it’s popularly believed that a “sugar rush” gives us energy.
But a study published in Neuroscience and Biobehavioral Reviews in April suggests that sugar can make us feel worse rather than boost our moods.
The German and UK researchers collected data from 31 studies involving nearly 1,300 adults. They studied the effect of sugar on various aspects of mood, including anger, alertness, depression and tiredness.
They found that people who have too much sugar become more tired and less alert within an hour and that these feelings become more intense over time.
According to the researchers, when people take in sugar their blood sugar levels rise rapidly, leading to a burst of energy and a short “feel good” period. However, as they begin to digest the sugar, their blood sugar levels decrease quickly leading to a bad feeling.
To remain on a “high” people are likely to eat more and more sugar until they become addicted to it. As with caffeine, this prevents the body from relaxing, leaving people feeling tired and less alert.
But the study findings needn’t make us think we must give up sweet food altogether. According to the World Health Organization, it is healthy to have the sugars found naturally in fruit, vegetables and milk so long as these make up less than 5 percent of daily total energy intake.
So the next time you feel tired and can’t concentrate, perhaps you should think twice before you bite into a chocolate bar. Maybe a spot of exercise at midday would be a better idea!
Tips for beating afternoon fatigue.
* Head outside and sit in the daylight for 10 minutes.
* Get into the routine of a mid-afternoon cup of tea.
* Plan group activities for midday.
* Add variety to your routine.
1.What does the underlined word “boost” in Paragraph 2 probably mean?
A.harm B.improve C.control D.change
2.How did the people feel after they had sugar in the study?
A.They felt more tired. B.They felt relaxed.
C.They were more alert. D.They felt energetic.
3.What do we learn from Paragraphs 5-6?
A.Our mood is connected to our blood sugar levels.
B.Taking in more sugar benefits mental health.
C.Getting caffeine is another way to relax.
D.Sugar and caffeine are all the same.
4.What would the author suggest people do when they are tired?
A.Give up sweet food. B.Have a bar of chocolate.
C.Do an hour of exercise. D.Eat foods with natural sugars.
高三英语阅读理解简单题查看答案及解析
On May 12,2008, a terrible earthquake happened in Sichuan, _____ the people are suffering.
A. from their effects B. of which effects
C. of its effects D. from whose effects
高三英语单项填空中等难度题查看答案及解析