1 . The fertile land of the Nile delta is being eroded (侵蚀) along Egypt’s Mediterranean coast at an astonishing rate, in some parts estimated at 100 metres per year. In the past, land washed away from the coastline by the currents of the Mediterranean Sea used to be replaced by sediment (沉淀物) brought down to the delta by the River Nile, but this is no longer happening.

Up to now, people have blamed this loss of delta land on the two large Aswan dams in the south of Egypt, which hold back almost all of the sediment that used to flow down the river. Before the dams were built, the Nile flowed freely carrying huge quantities of sediment. But when the Aswan dams were constructed to provide electricity and irrigation, and to protect the huge population centre of Cairo from annual flooding and drought, most of the sediment with its natural fertilizer accumulated up above the dam in the southern upstream half of Lake Nasser, instead of passing down to the della.

Now, however, there turns out to be more to the story. It appears that the sediment-free water picks up sand as it erodes the river bed and banks on the 800-kilometre trip to Cairo. Daniel Jean Stanley of the Smithsonian Institute noticed that water samples taken in Cairo indicated that the river sometimes carries more than 850 grams of sediment per cubic metre of water — almost half of what it carried before the dams were built.

International environmental organizations are beginning to pay closer attention to the region, partly because of the problems of erosion and pollution of the Nile delta, but mainly because they fear the impact this situation could have on the whole Mediterranean coastal ecosystem.

But there are no easy solutions. In the immediate future, Stanley believes that one solution would be to make artificial floods to flush out the delta waterways, in the same way that natural floods did before the construction of the dams. He says, however, that in the long term an alternative process such as desalination (脱盐) may have to be used to increase the amount of water available.

1. What stopped the sediment coming down to the delta?

A．The Mediterranean Sea.	B．The River Nile.
C．The Aswan dams.	D．Lake Nasser.

2. Why were the Aswan dams built?

A．To flush out the river beds.

B．To offer electricity and protection.

C．To make the water in the River Nile clean.

D．To keep the soil in the region nearby nutrient-rich.

3. What can we infer from the third paragraph?

A．There is no need to worry about the delta.

B．The methods of measurement need improving.

C．Whether the situation is good or not remains to be seen.

D．The dams’ consequences are beyond people’s expectation.

4. What is the last paragraph mainly about?

A．Difficulties to be settled.

B．Rewards for the challenge.

C．Severe influence of the situation.

D．Possible solutions to the problem.

2 . The measurable threat to the environment has been worsened by the spread of COVID-19 that increases the need for plastic protective equipment. Most plastic is made from fossil fuels. Millions of tons of greenhouse gas are released from the development of these resources and plastic production and burning.

The end life of plastic is just worrisome. Less than 10% of the plastic produced has been recycled. Even more of it has been burned. But the vast majority of plastic has been buried inland, and it is increasingly polluting the environment. We hear mostly about ocean plastic and the harm done to sea creatures that mistake plastic bags and bits for food. But microplastic is even more worrisome. Plastic doesn't break down biologically but instead breaks down into tiny particles（a very small piece of something）, which have been found in every corner of the planet, on land and in the air, in drinking water and food sources.

Yet the public has not given this global environmental disaster the attention it requires. Instead, they have viewed single-use plastic—which makes up about 40% of plastic used each year—as a litter issue that can be solved through better recycling and waste management. That attitude must change because the recent global breakdown of the market for recycling has made it clear that it has never been, nor ever will be, able to keep up with plastic trash use.

California has been the forerunner of plastic waste reduction—it was the first state to ban single-use plastic bags and may be the first state to transform the way goods are packaged. The state also came close to passing an act which would have required that products sold in plastic packaging in the state have a proven recycling rate of 75% by 2032. California, though influential, can't solve this crisis alone. The US has long been producing a great amount of plastic trash and it should engage in reducing the use of plastic as well.

1. Why does the author mention the release of greenhouse gas in paragraph 1?

A．To show the harm of plastic

B．To warn of the climate change.

C．To call for the development of fossil fuels.

D．To highlight the importance of plastic equipment.

2. What's the author's attitude towards the public opinion on single-use plastic?

A．Favorable.	B．Tolerant.
C．Curious.	D．Opposed.

3. What's California's role in reducing plastic waste?

A．A pioneer.	B．A failure.
C．An objector.	D．A predictor.

4. What can be the best title for the text?

A．Microplastic Products Are Harmful

B．Waste Recycling Is an Urgent Matter

C．Plastic Waste Pollution Is a Wake-up Call

D．Global Environmental Disasters Are Increasing