[单项选择]

We know that we have to pay for what we get. If we buy food, we know there will be a bill to pay. These are private bills. But there are also public bills that must be paid. Public bills are paid by the government. In turn, we get these services through taxes. What would happen if everyone in the city stopped paying taxes The water supply would stop; water might become unclean and impure. The streets might not be cleaned. There would be no police force to protect people and property. Schools would be closed. People would become sick and diseases might spread. We should not want to live in such a city. We all want pure water and food, clean streets and good schools. We want the police to prevent crime. The chief duty for every government is to protect persons and property. More than three quarters of the money spent by our government is used for this purpose. The next largest amount of public money goes to teach and train our citizens. Billions of dollars each year are spent on sc
A. Education.
B. Administration.
C. Public security.
D. Transportation.

[单项选择]

We know that we have to pay for what we get. If we buy food, we know there will be a bill to pay. These are private bills. But there are also public bills that must be paid. Public bills are paid by the government. In turn, we get these services through taxes. What would happen if everyone in the city stopped paying taxes The water supply would stop; water might become unclean and impure. The streets might not be cleaned. There would be no police force to protect people and property. Schools would be closed. People would become sick and diseases might spread. We should not want to live in such a city. We all want pure water and food, clean streets and good schools. We want the police to prevent crime. The chief duty for every government is to protect persons and property. More than three quarters of the money spent by our government is used for this purpose. The next largest amount of public money goes to teach and train our citizens. Billions of dollars each year are spent on sc
A. By taxing public services.
B. By providing needed services.
C. By making people pay for private bills.
D. By collecting taxes.

[填空题]What do we know about sea Most of us have seen it. Many of us have swum in it. We know that it looks very pretty when the sun is shining on it. And we also know that the sea is full of waves. Waves are beautiful to look at, but they can (11) ships at sea, as well as houses and buildings near the shore. What causes waves Most waves are caused by winds blowing over the (12) of the water. The sun heats the earth, causing the air to rise and the winds to blow. The winds blow across the sea, pushing little waves into enormous ones. When the wind is blowing at 120 (13) per hour, most waves will be about 12 meters high. In 1933 the United States (14) the largest measured wave in history. It rose in the Pacific Ocean to a (15) of 34 meters.

[单项选择]What should we know while claiming scientific knowledge of "human nature"
A. The variations in the human physique.
B. The similarities in human physique.
C. How people from different cultures solve their problems.
D. What all human beings have in common.

[填空题]We have chosen what we believe to be the five most spectacular natural wonders—those that are the biggest, longest or most impressive of their kind. These natural wonders inspire awe (敬畏) in everyone who views them.
Mt. Everest
Mt. Everest, which is located at the border between China and Nepal, is the world’s highest mountain. It measures 29,035 feet. And the mountain is still growing! Geological forces push it up a few millimeters each year.
Grand Canyon
Visitors to the Grand Canyon of the Colorado River in Arizona admire its breathtaking colors, rock formations and cliffs. No picture can adequately capture its beauty. The canyon is 277 miles long and from 4 to 18 miles wide.
Great Barrier Reef
The Great Barrier Reef extends 1,200 miles along Australia’s northeast coast through the Coral Sea. It is the largest coral formation in the world and is visible from space! Actually, it is not one ree