[简答题]One might ask why speculation is permitted when there is so real a danger of loss. The basic reason is that speculation can perform useful functions in the economy. Buying a commodity or stock, in the belief that prices will rise speeds market equilibrium and encourages faster entry of more suppliers. If the price change lagged until after an actual commodity shortage had occurred, the fluctuation would probably be sharper and more sudden. Remedial supply action could not be further delayed. Similarly, if speculators foresee a surplus in some commodity, their selling of futures will help drive the price down to some extent before the surplus actually occurs. When speculators foresee a shortage and bid up the price, they are also helping to conserve the present supply. As the price goes up, less of the commodity is purchased; a rise in price encourages users to economize. Similarly, a lowering of price encourages users to buy more, thus helping to sell the surplus which is developing.

[简答题]One might ask why speculation is permitted when there is so real a danger of loss. The basic reason is that speculation can perform useful functions in the market equilibrium and encourages faster entry of more suppliers. If the price change lagged until after an actual commodity shortage had occurred, the fluctuation would probably be sharper and more sudden. Remedial supply action could not be further delayed. Similarly, if speculators foresee a surplus in some commodity, their selling of futures will help drive the price down to some extent before the surplus actually occurs. When speculators foresee a shortage and bid up the price, they are also helping to conserve the present supply.

[填空题]When (ask) （） why he came to the exhibition, he said that he had been interested in oil paintings for years.

[填空题]When (ask) ______ why he came to the exhibition, he said that he had been interested in oil paintings for years.

[填空题]When (ask)_______why he came to the exhibition, he said that he had been interested in oil paintings for years.

[简答题]Burning garbage might be one kind of energy source that we can use to help meet our energy needs. (Passage 2)

[填空题]The restaurant was prosecuted when it was found that the food served Was not ______ (达到消费标准).

[单项选择]Ask why most people are right-handed, and the answer might fall along the same lines as why fish school(鱼成群地游). Two neuroscientists suggest that social pressures drive individuals to coordinate their behaviors so that everyone in the group gets an evolutionary edge.
Approximately 85 percent of people prefer their right hand, which is controlled by the left hemisphere of the brain. One theorized benefit of locating a particular function in one hemisphere is that it frees the other to deal with different tasks. But that idea does not explain why. population-wide trends for handedness exist in the first place.
Moreover, evidence gleaned in recent years has overturned the long-held belief that human handedness is a unique by-product of brain specialization attributable to language. A suite of studies has revealed brain lateralization in species from fish to primates(灵长类). Last August, for instance, scientists discovered that in the wild, chimpanzees show hand preferences.
Th
A. it was a necessary evolutionary process
B. it has something to do with human right-handedness
C. they need to coordinate with other fish
D. their brain function is unique

[填空题]Eating When One Feels Hungry

[单项选择]According to the passage, when stamps were used the postage would be ______ that in the early 19th century.

[单项选择]How does the man respond when the woman decides they should go on a diet
A. He agrees at once.
B. He hesitates.
C. He is indifferent to the idea.
D. He rejects the idea immediately.

[单项选择]Raising one's open hand with palm down to one's throat means" （　） "in English culture.
A. Shame on you.
B. I'm full.
C. Kill yourself.
D. You're shorter than I.