Here comes one of the two assignments for this cou...

Global warming is the gradual increase of the temperature of the earth's lower atmosphere as a result of the increase in greenhouse gases since the industrial Revolution. The temperature of the atmosphere near the earth's surface is warmed through a natural process called the greenhouse effect. Visible, shortwave light comes from the sun to the earth, passing unimpeded through a blanket of thermal, or greenhouse, gases composed largely of water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Infrared radiation reflects off the planet's surface toward space but does not easily pass through the thermal blanket. Some of it is trapped and reflected downward, keeping the planet at an average temperature suitable to life, about 60°F (16℃).

Growth in industry, agriculture, and transportation since the Industrial Revolution has produced additional quantities of the natural greenhouse gases plus chlorofluorocarbons and other gases, augmenting the thermal blanket. It is generally accepted that this increase in the quantity of greenhouse gases is trapping more heat and increasing global temperatures, making a process that has been beneficial to life potentially disruptive and harmful. During the past century, the atmospheric temperature has risen 1.1°F (0.6℃), and sea level has risen several inches. Some projected, longer-term results of global warming include melting of polar ice, with a resulting rise in sea level and coastal flooding; disruption of drinking water supplies dependent on snow melts; profound changes in agriculture due to climate change; extinction of species as ecological niches disappear; more frequent tropical storms; and an increased incidence of tropical diseases.

Among factors that may be contributing to global warming are the burning of coal and petroleum products (sources of carbon dioxide, methane, nitrous oxide, ozone); deforestation, which increases the amount of carbon dioxide in the atmosphere; methane gas released in animal waste; and increased cattle production, which contributes to deforestation, methane production, and use of fossil fuels.

Much of the debate surrounding global warming has centered on the accuracy of scientific predictions concerning future warming. To predict global climatic trends, climatologists accumulate large historical databases and use them to create computerized models that simulate the earth's climate. The validity of these models has been a subject of controversy. Skeptics say that the climate is too complicated to be accurately modeled, and that there are too many unknowns. Some also question whether the observed climate changes might simply represent normal fluctuations in global temperature. Nonetheless, for some time there has been general agreement that at least part of the observed warming is the result of human activity, and that the problem needs to be addressed.

A UN Conference on Climate Change, held in Kyoto, Japan, in 1997 resulted in an international agreement to fight global warming, which called for reductions in emissions of greenhouse gases by industrialized nations. Not all industrial countries, however, immediately signed or ratified the accord. In 2001 the G. W. Bush administration announced it would abandon the Kyoto Protocol: because the United States produces about one quarter of the world's greenhouse gases, this was regarded as a severe blow to the effort to slow global warming. Despite the American move, most other nations agreed later in the year (in Bonn, Germany, and in Marrakech, Morocco) on the details necessary to convert the agreement into a binding international treaty, which came into force in 2005 after ratification by more than 125 nations.

Which process caused the increased temperature?

A．Global warming.

B．Greenhouse effect.

C．Water evaporation.

D．Light reflection.

One of the teachers rewards is that he is using his mind on valuable subjects. All over the world people are spending their lives either on doing jobs where the mind must be kept numb(麻木的)all day, or else on highly rewarded activities which are tedious. One can get accustomed to operating an adding-machine for five and a half days a week, or to writing advertisements to persuade the public that one brand of cigarettes is better than another. Yet no one would do either of these things for its own sake. Only the money makes them tolerable. But if you really understand an important and interesting subject, like the structure of the human body or the history of the two World Wars, it is a genuine happiness to explain them to others, to welcome every new book on them, and to learn as you teach. With this another reward of teaching is very closely linked. That is the happiness of making something. When the pupils come to you, their minds are only half-formed, full of black spaces and vague notions and over simplifications. You do not merely insert a lot of facts, if you teach them properly. It is not like injecting 500 C. C. of serum(血浆), or giving a years dose of vitamins. You take the living mind, and mould it. It resists sometimes. It may lie passive and apparently refuse to accept anything you print on it. Sometimes it takes the mould too easily, and then seems to melt again and become featureless. But often it comes into firmer shape as you work, and gives you the incomparable happiness of helping to create a human being. To teach a boy the difference between truth and lie in print, to start him thinking about the meaning of poetry or patriotism, to hear him hammering back at you with the facts and arguments you have helped him to find, sharpened by himself and fitted to his own powers, gives the sort of satisfaction that an artist has when he makes a picture out of black canvas and chemical colorings, or a doctor when he hears a sick pulse pick up and carry the energies of new life under his hands.

What makes people tolerant of tedious jobs is______.

A．the job itself

B．the money

C．the significance of the job

D．the fact that it can keep the mind numb

Watch out! Here comes London Mayor Boris Johnson riding a bicycle from his new bike hire plan. “What we've put in is a new form. of public transport．These bikes are going to belong to everybaby．”

More than 12.000 people have signed up for the plan. They each receive a key at a cost of three pounds, with costs at one pound for a 24.hour membership. five pounds for seven days, and 45 pounds for an annual membership.

John Payne, a London teacher who cycles a lot, is among the first to usr the system．“It's very comfortable．For people who don't cycle much I think it'll be very useful. But for people who cycle regulary．they are possibly a bit slow．But they're perfect for London streets．very strong．I think they'll be very widely used.”

And Johnson says it's of good value．“I think it's extremely good value．The first half hour is free．If you cycle smart and you cycle around Londeon—most journeys in London take less than half an hour．you can cycle the whole day free．” Some 5.000bikes are currently available at over 300 docking stations(租车点)in central London. Johnson says the city will gradually expand the system．“Clearly one of our ambitions is to make sure that in 2012 when the world comes to London. they will be able to use London hire hikes to go to the Olympic stadiums.”

Mayor Boris Johnson is riding a bicycle to______．

A．go to work

B．attend a competition

C．promote his bike hire plan

D．show his love for cycling

Watch out! Here comes London Mayor Boris Johnson riding a bicycle from his new bike hire plan. “What we've put in is a new form. of public transport．These bikes are going to belong to everybaby．”

More than 12.000 people have signed up for the plan. They each receive a key at a cost of three pounds, with costs at one pound for a 24.hour membership. five pounds for seven days, and 45 pounds for an annual membership.

John Payne, a London teacher who cycles a lot, is among the first to usr the system．“It's very comfortable．For people who don't cycle much I think it'll be very useful. But for people who cycle regulary．they are possibly a bit slow．But they're perfect for London streets．very strong．I think they'll be very widely used.”

And Johnson says it's of good value．“I think it's extremely good value．The first half hour is free．If you cycle smart and you cycle around Londeon—most journeys in London take less than half an hour．you can cycle the whole day free．” Some 5.000bikes are currently available at over 300 docking stations(租车点)in central London. Johnson says the city will gradually expand the system．“Clearly one of our ambitions is to make sure that in 2012 when the world comes to London. they will be able to use London hire hikes to go to the Olympic stadiums.”

Mayor Boris Johnson is riding a bicycle to______．

A．go to work

B．attend a competition

C．promote his bike hire plan

D．show his love for cycling