1）Clay is p________ substance.

In a physical change no new substance is formed，__________ in the composition of matter.

A．nor does any change take place

B．nor any change takes place

C．not any change takes place

D．either any change takes place

No matter what substance it may be, it is ________ atom.

A．resulted from

B．formed

C．made up of

D．made up with

water is the most common substance(物质) found on the earth, but less than 1% of the earth’s water is suitable for drinking. more than 1,000,000,000 people around the world survive on just over 1 galon of water a day. probebly more than 3,000,000,000 people may suffer from not having enough water by the year 2025. you are considered lucky if you live in a country where you can drink water out of your kitchen tap or bathroom tap. people in some countries have to pay for drinking water at home. so clean water is one of our most valuabe natural resources(资源).
in fact, peole waste so much clean water today. in factories lots of water is wasted. at home many people are not taking showers but still baths, and many are brushing their teeth with the tap turned on. children are no longer taught how to save water….
you can save clean water in many ways. for example, if you keep gold fish, the *** water excellent for graden plants. and when you wash a milk bottle, pour the water on your house plants. putting a brick or a water into your toilet *** many help use less water, saving many gallons over a long time.
using rainwater is another simple way to save clean water. you can use rainwater to wash your hands after gardening, flush the toilet, and wash your car, your pet, your driveway when they are dirty.
for the same reason, people in malaysia are encourageed to use rainwater. if one has a house with a small garden, he would buy a huge plastic *** to keep rainwater for their daily life.
小题1:we can learn from the passage ______.

a．when man can’t live without water

b．where there is no water resource

c．why there is less water on the earth

d．how important it is to save water

小题2:according to the passage, one of the ways to save water is _______.

a．to stop keeping gold fish

b．to pay much for drinking water

c．to use it in a clever way

d．to educate those who waste water

小题3:the underlined word “flush” in paragraph 4 means “_______”.

a．clean something with water

b．pour water over something

c．make somehting wet with water

d．get water out of someghing

小题4:people are ecouraged to use rainwater _______.

a．so that is can make our life easier

b．so that clean water can be kept for other uses

c．because is it free and easy to get

d．because there is no claen water left for them

For several years, scientists have been testing a substance called interferon(干扰素), a possible wonder drug that is proving to be effective in treating a variety of diseases, including virus infections, bacterial infections, and cancers. To date, the new drug has no side effect of great influence to discourage its use. But in spite of its success, last year only one gram was produced in the entire world.
The reason for the shortage lies in the structure of interferon. A special protein, the interferon produced from one animal species cannot be used in treating another animal species. In other words, to treat human beings, only interferon produced by human beings may be used. The drug is produced by infecting white blood cells with a virus. Fortunately, it is so effective that the amount given to each patient each time is very small.
Unlike antibiotics (抗生素), interferon does not attack germs directly. Instead, it protects healthy cells from being infected, and prevents the reproduction of viruses within cells.
As you might conclude, one of the most special uses of interferon has been in the treatment of cancer. Dr. Hans Strander, a research physician at Sweden’s famous Karolinska Institute, has treated more than one hundred cancer patients with the new drug. Among a group of selected patients who had received operations for advanced cancer, half were given traditional treatments and the other half were given interferon. Among those treated with interferon 70 percent of them remained alive over three years, as compared with only 10 to 30 percent among those who had received the traditional treatments.
In the United States, a large-scale project supported by the American Cancer Society is now under way. If the experiment were successful, interferon could become one of the greatest medical discoveries of our time.
小题1:What is the difference between antibiotics and interferon?

A．Interferon has serious side effects, while antibiotics do not.

B．Antibiotics kill germs by attacking them directly, while interferon does not.

C．Antibiotics are very effective, while the effect of interferon is limited.

D．They are different in structure, although they are both proteins.

小题2:According to the passage, if 170 cancer patients received interferon treatment, how many of them would remain alive over three years?

A．About 30.

B．About 50.

C．About 120.

D．About 70.

小题3:The passage tells us that ________.

A．it is difficult to produce interferon in large quantities because of its special structure.

B．interferon is produced widely in lots of countries.

C．few of the patients who had received traditional treatments remained alive.

D．most of the patients who received interferon also needed traditional treatments.