4 . Plastic is low-cost and long-lasting. It is not easily degraded(降解) because natural degradation processes can’t deal with its chemical components(成分). It takes in other ocean-present harmful substances. These chemical and dangerous components are gradually got into the atmosphere with additives such as color, which turns out to be really harmful when the plastic breaks down.

The design and development of new plastic products was sped up after World War II. Life without plastic seemed impossible in the modern age. But even though plastic was quite convenient, the dark side of it was seen as people began to enjoy the throw-away community. Many plastic products, such as plastic bags, have a lifetime of a few minutes to hours. However, they’ll stay in the environment for hundreds of years. We are destroying the very world that nurtured us.

Just 9% of plastic has been recycled and 12% burnt after production rose in the 1950s, which leave s about 79% of the 8.3 billion tons produced sitting in landfills(垃圾填埋场) or damaging our fields, oceans, and waterways. And each year the plastic ends up as contaminants. So to beat plastic pollution, we need to work together.

While plastic burning reduces the amount of waste dumped into oceans and lands, harmful gases are still produced, which also leads to greenhouse gases. However, if we make a firm decision and use modern waste management methods, we will be able to create a safe and healthy world. It is high time that we as responsible global citizens, took on the duty of protecting our environment and made great effort in saving our mother earth, instead of just leaving everything to our government. So, ladies and gentlemen, let’s make a promise to successfully deal with plastic waste and protect our world from all possible risks.

5 . Naturalist Enzo Suma, who is now 40, lives in Puglia, a region in southern Italy whose long coastline faces the Adriatic Sea. Floating waste accumulates in this relatively enclosed part of the Mediterranean, unlike the open ocean, where the waste tends to be spread over a vast area. Feeling concerned about that, Suma makes it a habit to pick up the washed-up waste along the shore, especially after big winter storms.

One day, Suma was walking along the beach near his home when he discovered a bottle of Coke. Suma noticed on the bottle that the price, clearly printed on the bottom, was in lire, a currency (货币) that hadn’t been used in Italy since it was replaced by the euro in 2002. Could a plastic container have well survived in the Mediterranean, he wondered, for about two decades?

That led him to founding the Archeoplastica museum. It has a collection of about 500 unique pieces recovered from Italian shores and the Coke bottle is the first one of them. All collection demonstrates the unsettling life force of plastic waste in the environment. “Seeing that a product people may have used 30, 40, or 50 years ago remains still unchanged, you’ll feel different. It’s a great shock,” Suma said to a reporter. So Suma often exhibits selected pieces from the Archeoplastica collection at local schools around his hometown of Ostuni.

“The playful side of the work allows you to arrive at the less beautiful side of things,” Suma acknowledged. “Plastic is a kind of useful substance. But it’s unthinkable that a water bottle, made from a material designed to last so long, can be used for just a few days—or even minutes—before becoming garbage. Clean the beaches. Clean the oceans. Recycle. But if we are still throwing out plastics, none of those are going to be long-term solutions.”

Nowadays, our living conditions are becoming increasingly serious owing to the destruction of our environment. Many plants and     1    (animal) are endangered, and all the food chain has been destroyed,     2     has aroused a wide concern among people.

It is obvious that there are many reasons     3     this phenomenon. Firstly, the overuse of natural resources has a bad effect on     4     balance of natural ecology. Secondly, the population of the world is increasing rapidly, making the world too     5     (crowd) for us to live in. Thirdly, it is the smoke released from factories and cars that     6     (pollute) the environment badly.

Personally, I hold the view that effective measures must be taken     7     (improve) the present situation. To begin with, the government must     8     (sure) pass laws to prevent people from throwing rubbish everywhere, and prevent factories from harming the environment. Besides, as a member of the society, we are bound to do something for environmental     9     (protect), such as planting more trees,     10     (recycle) natural resources and so on. I’m sure that things will be better in the near future if we insist on doing like this.

Factory farming involves     1     (keep) farm animals inside buildings to increase the production of meat or eggs. According to an institute, “74% of the world’s poultry, 43% of its beef and 68% of its eggs     2     (produce) in this way.”

The main     3     (argue) for factory farming is that, apart from being a lot cheaper than     4     (tradition) or organic farming, it     5     (provide) more food for a world population that has already reached seven billion. As factory farms do not use many workers, the costs are low and the production is high. Moreover, factory-farmed animals suffer from     6     (few) diseases than those living outside.

On the other hand, opponents of factory farming say that it is cruel to the animals. For instance, many farm animals are kept in small spaces     7     they can hardly move. In addition to this, factory farming has a negative impact     8     the environment because it creates a lot of waste products, and uses a lot of chemicals to control insects and drugs     9     (treat) diseases.

To sum up, despite producing cheap food, factory farming is bad for the planet and for the animals themselves. We should try to reduce this kind of farming, although we would have to pay more for our eggs     10     meat.

10 . London is in a valley. So towns in valleys see the surrounding air staying to the lower point. During the night, cold air from surrounding hills falls down in the valleys. The fog reputation of London, which called the smog, comes from the fact that the houses were, in the past, heated by coal. Houses and factories gave off much pollution in the air and, in order to condense (浓缩) into tiny water droplets, moisture (湿度) needs to be in contact with something that has a mass. So, the valley, the city, the coal heating, a high pressure with no wind and staying air... and you get the London’s smog.

In common with many countries, Britain has serious environmental problems. In 1952,more than 4,000 people died in London because of the worst smog. The government introduced new laws to stop smog from coal fires and factories and the situation improved a lot.

Today, London is much cleaner but there is a new problem: smog from cars. In December 1991,there was very little wind in London and pollution increased a lot. As a result, about 160 people died from pollution in just four days.

Part of the problem is the new “out of town” shopping centers. In the past, people often walked to shops near their homes or went by bus. Now, many people drive to the new shopping centers. As a result, the small shops have disappeared and more people have to travel to do their shopping.

Many people are trying to reduce the use of cars in Britain. Some cities now have special bicycle paths and many people cycle to work. Some people also travel to work together in one car to reduce the pollution and cost.

Sometimes people take “direct action”. In 1995,for example, many people wanted to stop a new road from being built near Newbury. They set up houses in trees and lived there for many months. It took a long time to force the people out of the trees before the construction work on the road could continue.