[单项选择]

The United States government publishes guidelines for appropriate nutrient intakes. These are known as the Recommended Dietary Allowances (RDAs) and are updated regularly based on new research in nutrition. RDAs are suggested amounts of calories, protein, and some minerals and vitamins for an adequate diet. For other dietary substances, specific goals must await further research. However, for the U.S. population as a whole, increasing starch and fiber in one’’s diet and reducing calories (primarily from fats, sugar, and alcohol) is sensible. These suggestions are especially appropriate for people who have other factors for chronic diseases due to family history of obesity, premature heart disease, diabetes, high blood pressure, and high blood cholesterol, or for those who use tobacco. Snacks can furnish about one-fourth of the calorie requirements among teenagers. Those snacks should also provide much of the day’’s allowances for protein, minerals, and vit
A. The time of day when food is consumed affects its nutritive value.
B. Different foods can be combined to increase total nutrition value.
C. It can be detrimental to your health to eat breakfast foods later in the day.
D. When food is eaten has no bearing on its nutritive effects.

[单项选择]

The United States government publishes guidelines for appropriate nutrient intakes. These are known as the Recommended Dietary Allowances (RDAs) and are updated regularly based on new research in nutrition. RDAs are suggested amounts of calories, protein, and some minerals and vitamins for an adequate diet. For other dietary substances, specific goals must await further research. However, for the U.S. population as a whole, increasing starch and fiber in one’’s diet and reducing calories (primarily from fats, sugar, and alcohol) is sensible. These suggestions are especially appropriate for people who have other factors for chronic diseases due to family history of obesity, premature heart disease, diabetes, high blood pressure, and high blood cholesterol, or for those who use tobacco. Snacks can furnish about one-fourth of the calorie requirements among teenagers. Those snacks should also provide much of the day’’s allowances for protein, minerals, and vit
A. protein
B. fats
C. starch and fiber
D. sandwiches

[单项选择]
The United States is a federal union of 50 states. The capital of national government is in Washington D. C. ( District of Columbia). The federal constitution sets up the structures of the national government and lists its powers and activities. The constitution gives Congress the authority to make laws which are necessary for the common defense and the good of the nation. It also gives the federal government the power to deal with national and international problems that involve more than one state. All powers that are not given to the federal government by the constitution are the responsibility of the individual states.
The federal government has three branches - the executive, the legislative, and the judicial. The legislative branch makes the laws, executive branch carries out the laws, and judicial branch interprets the laws. The President heads the executive branch and the Supreme Court heads the judicial b
A. The Congress.
B. The Federal government.
C. The President.
D. The Supreme Court.

[单项选择]

A government agency publishes ratings of airlines, ranking highest the airlines that have the smallest proportion of late flights. The agency’s purpose is to establish an objective measure of the relative efficiency of different airlines’ personnel in meeting published flight schedules.
Which one of the following, if true, would tend to invalidate use of the ratings for the agency’s purpose（）

A. Travelers sometimes have no choice of airlines for a given trip at a given time
B. Flights are often made late by bad weather conditions that affect some airlines more than others
C. The flight schedules of all airlines allow extra time for flights that go into or out of very busy airports
D. Airline personnel are aware that the government agency is monitoring all airline flights for lateness
E. Flights are defined as "late" only if they arrive more than fifteen minutes past their scheduled arrival time, and a record is made of how much later than fifteen minutes they are

[填空题]The United States government imposed the first national income tax as early as in 1817.

[单项选择]According to the United States government, people are classified as homeless if they have no place to stay and no expectation of finding a place for the next thirty days, Although technically accurate, that is an impersonal assessment of an enormous and very human problem,
The homeless population represents all of us Americans, It includes men and women, the elderly, children, and infants. Its members are from all ethnic (种族的) groups. What they have in common is poverty.
Currently in the U.S., thirty-nine million people live in poverty. When money is really tight, paying the rent or buying food often becomes a choice. Government assistance in the form of food stamps does help but, as one homeless man explains, you can’t pay the rent with food stamps.
With no money for rent, the streets and homeless shelters become the alternative.The writer thinks that the U.S. government’s definition of the homeless reveals ______.
A. an insincere attitude toward the homeless

[填空题]The United States government wants to know what the public thinks about its findings on the safety of (36) animals.
The Food and Drug Administration says meat and milk from clones of adult cattle, pigs and goats are safe to eat. An FDA (37) called them "as safe to eat as the food we eat every day."
And when those clones (38) sexually, the agency says, their (39) are safe to eat as well. But research on cloned sheep is limited. So the FDA (40) that sheep clones not be used for human food.
The United States this year could become the first country to (41) the sale of foods from cloned animals.
First, however, the public will have ninety clays to (42) on three proposed documents. On December twenty-eighth the FDA released a long report, called a draft risk (43) , along with two policy documents.
(44) . The FDA seemed ready to act several years ago, but an adv