I will tell you the truth about plastic bags－the positive and the negative sides and provide a solution to this problem. Whether it is a shopping bag, a food bag or a trash bag, they are all made of plastic bags. Grocery store owners are very generous in using plastic bags. They place the fruit in one bag and drop the box of milk in another. Ever wonder why?
The positive side of plastic bags
Grocery stores, shopping centres, and restaurants are not thrifty in using and giving out plastic bags because they cost no more than a cent each, while a paper bag costs four cents. Plastic bags are produced so cheaply and massively（大量地）that they are used by 80% of store owners. In addition, they are light and very easy to carry and store.
The production of plastic bags has increased greatly over the last 20 years and producers of plastic bags are making large profits. However, the negative side of plastic bags is becoming well-known. More people are now getting worried that the earth is becoming a victim of the plastic bag success story.
The negative side of plastic bags
While production and consumption（消费）of plastic bags is good for business, it is not so for our Mother Earth. They have resulted in an increase in the amount of litter found floating in water or in the streets where we live.
Plastic storage bags, after usage, usually go to landfills（垃圾填埋地）as trash bags. They make the oceans poison sea animals. They give off toxins（毒素）when burned. They simply pollute the ground, air and water.
That is the true cost of plastic bags, and it looks like it is more than a cent. These are very alarming concerns and proper action needs to be taken.
【小题1】According to Paragraph 3, plastic bag producers ________.

Some teachers are unforgettable. They lead by example and never lose their smile. They change lives. Eileen Madden is one of them. Her students must think she was born with an eraser and a piece of chalk in her hand.
“It’s a joy to get up early every morning to be the first one here,” say the 55-year-old Holy Ghost School third grade teacher. Madden arrives shortly after 6 am to prepare her classroom and work on the school breakfast program.
“My family all went to St. Teresa’s School,” she says. “I always said, ‘One day, I’m going to come back and get one of those big desks.’”
With a watchful eye always on the lookout for “one of those big desks”, Madden returned to St. Teresa after graduating from college and taught second grade at the Olneyville neighborhood elementary school until it was burnt in a fire in 1990 and had to be closed. Madden then went to Holy Ghost School where she started as a second-grade teacher and then moved up one grade level.
“I take care of setting up and serving breakfast,” she says. “In winter it is still dark when I arrive here.” Madden praises Holy Ghost School Principal Carol Soltys and the school’s workers for their continued support. “It’s a family,” she said.
Her class is small this year with 15 students, including some from the Dominican Republic, Puerto Rico, Costa Rica, Haiti, Guatemala, Nigeria and Ghana. Madden admits that she’s encouraged by her former students, now grown-ups, who want their own children to enjoy a similar experience in a safe, good environment. “They tell others, ‘I send my child to Eileen Madden’s School, ’” she adds.
【小题1】What does the underlined sentence in Paragraph 1 suggest?

Our sun is a star, and nine worlds move round it. Worlds like these are planets (行星).
But there are other stars, other suns. Not only thousands of them, but millions of them. Do different stars have planets? We can see the planets round our own sun. But we haven’t seen any more. The stars are too far away from us. Stars give out (发出)light, but the planets don’t have any light of their own. So we can’t see them. They’re too far, and too dark.
Still, we can tell that some stars have planets. While a big planet goes round, it pulls its star to one side. And sometimes we can see this, Then we know that the star has a planet.
For example, Barnard’s Star（巴纳德星）is a small red star. And it is the quickest star in the universe. But sometimes it moves slower, and then quicker again. We have know Barnard’s Star for many years, and now we are sure it has a planet.
【小题1】A star is a large body in the universe.it________.

Imagine when you are sailing an ocean for the first time, you see a big fish swimming near your ship. You might be scared, and worried about whether it will turn over your ship for a meal. In fact, it is not a fish at all, but a gentle giant whale.
Whales are not fishes but mammals (哺乳动物). Their body temperature stays the same, and does not change with the temperature of their environment. They breathe air, so they have to come out of the water to get oxygen. Thus, they cannot afford to fall into a sleeping state for too long, since they need to be awake in order to breathe. It is thought that only half of their brains sleep at a time, so that whales are never completely asleep. Females give birth to the young. They have hair. Although they are not covered in hair or fur like many mammals, whales have some bristles (胡子), usually on their heads.
Whales are highly social animals with complex languages and intelligence. They communicate with each other using romantic sounds, called “whale songs”. Being so large and powerful, these sounds are also loud.
Whales are endangered as a result of whaling (捕鲸) from the eleventh century to the twentieth. It has attracted the attention of environmentalists and some measures (措施) have been taken to protect whales.
【小题1】How many aspects show that whales are mammals?

The need to feed a growing population is putting much pressure on the world’s supply of water. With 97% of the world’s water too salty to be drunk or used in agriculture, the worldwide supply of water needs careful management, especially in agriculture. Although the idea of a water shortage seems strange to someone fortunate enough to live in a high rainfall country, many of the world’s agricultural industries experience constant water shortages.
Although dams can be built to store water for agricultural use in dry areas and dry seasons, the costs of water redistribution (重新分配) are very high. Not only is there the cost of the engineering itself, but there is also an environmental cost to be considered. Where valleys are flooded to create dams, houses are lost and wildlife homes destroyed. Besides, water may flow easily through pipes to fields, but it cannot be transported from one side of the world to the other. Each country must therefore rely on the management of its own water to supply its farming requirements.
This is particularly troubling for countries with agricultural industries in areas dependent on irrigation. In Texas, farmers’ overuse of irrigation water has resulted in a 25% reduction of the water stores. In the Central Valley area of southwestern USA, a huge water engineering project provided water for farming in dry valleys, but much of the water use has been poorly managed.
Saudi Arabia’s attempts to grow wheat in desert areas have seen the pumping of huge quantities of irrigation water from underground reserves. Because there is no rainfall in these areas, such reserves can only decrease, and it is believed that fifty years of pumping will see them run dry.
【小题1】.
. From the first two paragraphs we learn that __________.

A．The underground water in Saudi Arabia might run out in 50 years.

B．Most industries in the world suffer from water shortages.

C．The water stores in Texas have been reduced by 75%.

D．Good management of water use resulted from the project in the Central Valley.