Rivers are the veins of the Earth, transporting the water and nutrients (营养物) needed to support the planet’s ecosystems, including human life. While many nutrients are essential to the survival of life, there is one element transported by water in rivers that holds the key to life and to the future of our planet — carbon.
Carbon is everywhere and understanding the way it moves and is either released or stored by the Earth system is a complex science in itself. Carbon starts its journey downstream when natural acid rain, which contains carbon dioxide from the atmosphere, melts minerals in rocks. This helps transform carbon dioxide to bicarbonate (碳酸氢盐) in the water that then flows in our rivers. This is a very long process, which is one of the main ways carbon dioxide is removed from the atmosphere. Carbon is transported by rivers to oceans and once that carbon reaches the ocean, it is stored naturally in deep sea sediments (沉淀物) for millions of years.
As carbon travels down a river, different processes may impact whether it continues to flow downstream or whether it is released into the atmosphere. For example, human engineering, like extensive dam construction, will result in dramatic changes to how water and sediments travel down the river. Some carbon that fails to reach the sea may return to the atmosphere in some way, which causes more warming.
Earth’s climate is closely related to the carbon cycle. We all know about the essential role of plants in consuming carbon dioxide, but do we know enough about rivers? Changing the chemistry and the course of rivers may have significant impacts on how they transport carbon. Remember: wherever we live, we all live downstream.
1.Where is the carbon in rivers originally from?
A.The atmosphere. B.The rocks.
C.The acid rain. D.The upstream areas.
2.Why is human engineering mentioned in Paragraph 3?
A.To show how important to life carbon is.
B.To explain how necessary it is to build dams.
C.To show how a natural process is interrupted.
D.To explain how humans fight global warming.
3.What does the author want to convey in the last paragraph?
A.We’d better move upstream to live.
B.We should protect plants along rivers.
C.We’d better seek more help from plants.
D.We should be cautious about river management.
4.What is the best title for the text?
A.What Humans Do with Rivers
B.How Rivers’ Transporting Carbon Counts
C.What the Carbon Cycle Means to Us
D.How Living Downstream Affects the Earth
My 12-year-old son Jack hit a milestone last summer. “Mom, I’m quitting the piano,” he said firmly.
Immediately, I said, “You can’t.” “Why?” he asked. “Because I said so.” And the battle followed. Many of you know the battle I am talking about. It’s the one where all of a sudden instrument that once filled the home with wonderful music are abandoned in favor of sports, games and all cool things. When Jack started piano lessons in the second grade, he took to music eagerly, displaying interest and talent. Over the next few years, he willingly entered competitions recommended by his teacher.
Much to our son’s sadness, my husband and I decided to stand firm. While parents allowed their children to win battles now and then, this was one that my husband and I were not willing to concede. We decided, however, to give him a choice of taking up another instrument. We suggested the guitar.
He was open to meeting a couple of instructors. “My hands are too small,” he complained. But the student who came after us was a 5-year-old girl.
I suggested changing teachers. He said he wanted a teacher who was “nice”. I understood that meant “no stress”. Finally, we found a male teacher with a gentle voice and a great sense of humor. He said that competitions were not his thing; playing music was.
After my son’s first lesson with his new teacher, I took a deep breath and braced myself for the usual negative complaints. “Mom, he makes me like the piano again,” my son announced as we headed to the car.
And then, cheerful piano music filled the house during the long winter evenings. The playing wasn’t as long as I would have liked or as frequent as it used to be. But it’s sweet, still the same.
1.What made Jack want to give up the piano?
A.Having no talent in music.
B.Having other cool things to do.
C.Failing in music competitions.
D.Being very busy with his lessons.
2.Why did Jack complain about his small hands?
A.To remind his mom of his weakness.
B.To show his embarrassment in learning.
C.To find an excuse to quit learning the guitar.
D.To prove the difficulty of playing the guitar.
3.What did Jack like his music teacher to do?
A.Play the guitar very well.
B.Not push him too much.
C.Help him win a competition.
D.Not report him to his parents.
听下面一段独白，回答以下小题。
1.What is expected tonight around five or six?
A.Ice. B.Rain. C.Snow.
2.How many inches of snow are predicted?
A.One or two. B.Three or four. C.Five or six.
3.Why did the high schools close?
A.The college has already shut.
B.The roads are dangerous to drive on.
C.The town is unprepared for the weather.
4.Which suggestion does the weatherman make?
A.Buying supplies. B.Closing the schools. C.Pushing snow off roads.
听下面一段较长对话，回答以下小题。
1.Whom is the party for?
A.Dan. B.Julie. C.Jane.
2.When will the guests arrive?
A.At 4:00. B.At 5:00. C.At 6:00.
3.What has been prepared?
A.A special cake. B.Drinks. C.Candles.
4.What happened in the party last year?
A.The police came.
B.The building caught fire.
C.The neighbors got drunk.
听下面一段较长对话，回答以下小题。
1.What do we know about the hotel in Sitges?
A.It's far from the beach.
B.It's beside a busy road.
C.It's near a bus stop.
2.What can people enjoy in the hotel?
A.Football games. B.KTV. C.Keep-fit classes.
3.What will the speakers do next?
A.Ask for a lower price.
B.Look around the hotel.
C.Explain to the manager.
听下面一段较长对话，回答以下小题。
1.What does the man think of literature?
A.It’s helpful. B.It’s hard. C.It’s interesting.
2.What subject does the woman like most?
A.Art history. B.Photography. C.Geography.
