单项选择题

The Intergovernmental Panel on Climate Change (IPCC) was set up in 1988 to assess information on climate change and its influence. Many hundreds of scientists from many countries participated in its preparation and review. Incorporating new results from the past five years of research on climate change, its third report in 2004 predicted global temperature rises by 2100 of between 1.4℃ and 5.8℃compared to a previous assessment of 1.0 to 3.5℃ for the same period. Although the issue of the changing climate is very complex and some changes are uncertain, temperature rises are expected to affect countries throughout the world and have a severe effect on sea- level rises.
Scientists have argued about whether temperature rises are due to human activities or due to natural changes in our environment. Some have believed that the emission of industrial and life wastes turns to warm the surface, while the others have insisted that natural factors, such as changes in solar output or explosive volcanic activity can also be criminal in this case.
The IPCC announced in 2001 that "most of the warming observed over the last 50 years is likely to be owing to human activities". This was a more forceful statement than in 1996 when the second report stated that there was a "definite human influence on the climate" which was the first time they had concluded such a link. Many experts believe the faster the climate changes, the greater the risk will be.
Key points of the predictions for climate change globally include that by the second half of the 21st century, wintertime rainfall in the northern areas will rise, that at the same time Australia, Central America and southern Africa are likely to see decreases in autumn rainfall, that some land areas in the tropics will see more rainfall, and that there will generally be more hot days over land areas.
The IPCC also warned that global surface temperature increases and rising sea level are predicted to continue for hundreds of years after stabilization of greenhouse gas concentrations, owing to the long timescales on which the deep ocean adjusts to climate change. Therefore, further research is required to improve the ability to detect, attribute and understand climate change, to reduce uncertainties and to project future climate changes.
According to the author, climate researchers ______.

[A] are quite sure about why it’s getting hotter and hotter
B. declare that we humans are the cause why it’s getting hotter
C. have discussed the possible causes why it’s hotter
D. have claimed that changes in nature are the roots of hot days.

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单项选择题

What do we know about the woman in her current job

[A] She is successful.
B. She is under pressure.
C. She is incompetent.
D. She is cautious.

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The word grubstake in paragraph 2 means ______. [A] to supply miners with food and supplies [B] to open a general store [C] to do one’s contribution to the development of the mine [D] to supply miners with food and supplies and in return get a share in the mine, if one was discovered

As it turned out, it was silver, not lead, that was to make Leadvill’s fortune and wealth. Tabor knew little about mining himself, so he opened a general store, which sold everything from boots to salt, flour, and tobacco. It was his custom to "grubstake" prospective miners, in other words, to supply them with food and supplies, or "grub", while .they looked for ore, in return for which he would get a share in the mine if one was discovered. He did this for a number of years, but no one that he aided ever found anything of value.
Finally one day in the year 1878, so the story goes, two miners came in and asked for "grub". Tabor had decided to quit supplying it because he had lost too much money that way. These were persistent, however, and Tabor was too busy to argue with them. "Oh, help yourself. One more time won’t make any difference," He said and went on selling shoes and hats to other customers, the two miners took $17 worth of supplies, in return for which they gave Tabor a one-third interest in their findings. They picked a barren place on the mountainside and began to dig. After nine days they struck a rich vein of silver. Tabor bought the other shares of the two men, and so the mine belonged to him alone. This mine, known as the "Pittsburgh Mine," made $1,300,000 for Tabor in return for his $17 investment.
Later Tabor bought the Matchless Mine on another barren hillside just outside the town for $117,000. This turned out to be even more fabulous than the Pittsburgh, yielding $ 35,000 worth of silver per day at one time. Leadville grew. Tabor became its first mayor, and later became lieutenant governor of the state.