[单项选择]By the mid-1960s, cotton farmers in Central America found that pesticides
A. were wiping out 50% of the pests plaguing the crops.
B. were destroying 50% of the crops they were meant to protect.
C. were causing a 50% increase in the number of new pests reported.
D. were costing 50% of the total amount they spent on their crops.

[单项选择]Cotton farmers in Central America began to use pesticides
A. because of an intensive government advertising campaign.
B. in response to the appearance of new varieties of pest.
C. as a result of changes in the seasons and the climate.
D. to ensure more cotton was harvested from each crop.

[单项选择]Climate change, （　） the unfortunate Central Americans have contributed virtually nothing seems to be increasing the ferocity of nature in the isthmus.
A. for which
B. in which
C. by which
D. to which

[填空题]Cotton farmers in the upper reaches of the Aral switched to rice growing in order to gain higher yields.

[填空题]The percentage of remarriage among divorced Americans is

[简答题]Please discuss Henry James’ contribution to American literature in regard to his representative works, themes, writing techniques and language.

[单项选择]Appealing to these expectations, Obama told Americans what they want to hear. People with insurance won’t be required to change plans or doctors; they’ll enjoy more security because insurance companies won’t be permitted to deny coverage based on "pre - existing conditions" or cancel policies when people get sick. All Americans will be required to have insurance, but those who can’t afford it will get subsidies.
As for costs, not to worry. "Reducing the waste and inefficiency in Medicare and Medicaid will pay for most of is plan. " Obama said. He pledged to" not sign a plan that adds one dime to our [budget] deficits- either now or in the future. "If you believe Obama, what’s not to like Universal insurance. Continued choice. Lower costs.
The problem is that you can’t entirely believe Obam
A. What is the author’s attitude towards Obama’s reform plan on health- care Welcome.B. Critical.C. Indifferent.D. Approvin

[简答题]Some of the most popular attractions across America are the many free concerts offered to the public throughout the year. These involve not only amateur performers, but professional artists as well. The public parks of many cities across the country usually have bandstands and large lawns. As a service to citizens, they rent out space to performers free of charge. Amateur groups, with nothing more than a desire to perform, offer their talents freely to the public. Semi. professional artists are pleased to get the chance to perform before the public to perfect their craft and nurture the hope of being discovered before beginning a professional career. Famous professionals also give free concerts to make contact with their admiring fans. Often such concerts are sponsored by a large corporate organization and offered to the public free of charge as a cultural service and support for the arts.
The free concerts feature all kinds of music from rock and roll, jazz, country-western to

[单项选择]The number of the Representatives from each American state depends on the ______ .
A. contribution a state has made to the nation
B. population of the state
C. size of the state
D. economic power of the state

[单项选择]A. Farmers relied less on imports.
B. Farmers became more dependent on bank loans.
C. The costs for shipping farm products by train increased.
D. Prices for farm products went up.

[单项选择]

Shortages of flu vaccine are nothing new in America, but this year’s is a whopper. Until last week, it appeared that 100 million Americans would have access to flu shots this fall. Then British authorities, concerned about quality-control problems at a production plant in Liverpool, barred all further shipments by the Chiron Corp. Overnight, the U.S. vaccine supply dwindled by nearly half and federal health officials found themselves making an unusual plea. Instead of beseeching us all to get vaccinated, they’re now urging most healthy people between the ages of 2 and 64 not to. "This reemphasizes the fragility of our vaccine supply, " says Dr. Martin Myers of the National Network for Immunization Information, "and the lack of redundancy in our system. "
Why is such a basic health service so easily knocked out Mainly because private companies have had little incentive to pursue it. To create a single dose of flu vaccine, a manufacturer has
A. America relies too much on foreign suppliers
B. the demand of flu vaccines is high this year
C. quality problem is a serious problem in flu vaccine production
D. the supply of flu vaccines is rather weak and America has no back-up measures to make it up