A. we all take jets on our journey

B. there are too many cars, buses and trucks along the roads

C. it makes a lasting attack on our ears

D. our hearing is a little harmed

3. A country stream may be polluted because ______.

A. the balance of nature has been changed

B. the water is no longer alive and sparkling

C. it is made dirty by petrol, cars, broken bottles and rotten vegetables

D. fish can't swim in the water

4. "we are endangering our sense of smell" means ______.

A. our sense of smell is being lost B. something is wrong with our noses

C. we can't smell with our noses any more D. smell is dangerous to some of us

5. Which of the following statements is not true?

A. The air pollution problem still exists although the "clean air" campaigns are carried out.

B. Advanced technology has brought us both advantages and pollution.

C. Fish swimming in the polluted water can kill the plants and animals living there.

D. When we are strolling by a country Stream or on a beach, we can smell something bad from the water.

When Americans consider families, many of them think of a 'traditional family.' A traditional family is one in which both parents are living together with their children. The father goes out and works and the mother stays home and rears the children. The biggest change in families in the United States is that most families today do not fit this image.

The most common type of family now is one in which both parents work outside the home. In 1950, only 20 percent of all American families had both parents working outside the home. Today, it is 60 percent. Even women with young children are going back to work. About 51 percent of women with children younger than one year old now work outside the home.

Another big change is the increase in the number of families that are headed by only one person, usually the mother. Between 1970 and 1988, the number of single-parent families more than doubled.