[单项选择]The Agricultural Adjustment Act encouraged American farmers to______.


A. reduce their scale of production
B. make full use of their land
C. adjust the prices of their farm products
D. be self-sufficient in agricultural production

[单项选择]The Agricultural Adjustment Act encouraged American farmers to ______.


A. reduce their scale of production
B. make full use of their land
C. adjust the prices of their farm products
D. be self-sufficient in agricultural production

[单项选择]Employees are encouraged to support the greening of the home office in ______ ways they feel most comfortable.
A. whenever
B. whichever
C. however
D. wherever

[单项选择]People are encouraged to use overhead bridges mainly because ______.


A. zebra crossing can be ignored
B. it is necessary to reduce traffic jam
C. they prevent accidents and loss of life
D. traffic is very heavy in large cities

[单项选择]Young people are encouraged to have more experiences because
A. they help to achieve success in the future.
B. they show one’s value.
C. they develop one’s potential.

[填空题]White collars are encouraged to write such messages "’upset", "busy", "obsessed by my work" and "need a rest" and post them on the walls in order to____________(缓解压力和紧张).

[单项选择]The scientist and agricultural innovator George Washington Carver aided the economy of the South by developing hundreds of commercial uses for crops such as the peanut.


A. restored
B. stabilized
C. helped
D. changed

[单项选择]

What did some agricultural producing nations complain about （）

A. The Doha Round of world trade talks hasn't been held for long.
B. Their farmers can not compete with artificially-low prices.
C. Developing countries cannot compete with developed ones

[单项选择]The Supreme Court rejected the Agricultural Adjustment Act because it believed that the Act ______.

[单项选择]The view of science fiction encouraged by pulp magazines, which may be wrong, is nevertheless__________.


A. popular
B. elegant
C. fashionable
D. deranged

[单项选择]Teachers in this school were encouraged to use drama as a(n) ______ of learning.
A. design
B. instrument
C. agency
D. tool

[单项选择] Diseases of Agricultural Plants
Plants, like animals, are subject to diseases of various kinds. It has been estimated that some 30,000 different diseases attack our economic plants; forty are known to attack corn, and about as many attack wheat. The results of unchecked plant disease are all too obvious in countries which have marginal food supplies. The problem will soon be more widespread as the population of the world increases at its frightening rate. Even in countries which are now amply fed by their agricultural products there could soon be critical food shortages. It is easy to imagine the consequences of some disastrous attack on one of the major crops; the resulting famines could kill millions of people, and the resulting hardship on other millions could cause political upheavals disastrous to the order of the world.
Some plants have relative immunity to a great many diseases, while others have a susceptibility to them. The tolerance of a particular plant changes as the growing conditions change. A blight may be but a local infection easily controlled; on the other hand it can attack particular plants in a whole region or nation. An example is the blight which killed virtually every chestnut tree in North America. Another is the famous potato blight in Ireland in the last century. As a result of that, it was estimated that one million people died of starvation and related ailments.
Plant pathologists have made remarkable strides in identifying the pathogens of the various diseases. Bacteria may invade a plant through an infestation of insect parasites carrying the pathogen. A plant can also be inoculated by man. Other diseases might be caused by fungus which attacks the plant in the form of a mold or smut or rust. Frequently such a primary infection will weaken the plant so that a secondary infection may result from9 its lack of tolerance. The symptoms shown may cause an error in diagnosis10, so that treatment may be directed toward bacteria which could be the result of a susceptibility caused by a primary virus infection.How many diseases are known to attack wheat
A. Around 30,000.
B. Around 140.
C. Around 29,960.
D. Around 40.

[单项选择]A) connected C) involved
B) encouraged D) participated


A. connected
B. encouraged
C. involved
D. participated

[单项选择]The students were much encouraged（）a chance to talk with the Americans in English.
A. to get
B. got
C. to have got
D. having got

[单项选择]The aim of voyages Maury encouraged in the 1840s was ______.


A. to make some sound experiments in the oceans
B. to collect samples of sea plants and animals
C. to estimate the length of cable that was to be made
D. to measure the depths of two oceans