21. How did John feel when he saw the old man?

A. Frightened. B. Regretful. C. Delighted. D. Comfortable.

22. Why did John buy the book?

A. He was interested in the super nature.

B. He wanted to have a company.

C. He wanted to help the old man.

D. He tried to act to be brave.

23. When did John turn to the last page of the book?

A. Immediately after he bought it.

B. When he was talking with his parents.

C. When he read to the last page of the book.

D. After he was woken up at midnight.

B

Dogs are known for their sense of smell．They can find missing people and things like bombs and

illegal drugs．Now a study suggests that the animal known as man’s best friend can even find

bladder（膀胱）cancer．

Cancer cells are thought to produce chemicals with unusual odors（气味）．Researchers think dogs

have the ability to smell these odors, even in very small amounts, in urine（尿）．The sense of smell in dogs is thousands of times better than in humans．

The study follows reports of cases where, for example, a dog showed great interest in a growth on the leg of its owner．The man was later found to be skin cancer．

Carolyn Willis led a team of researchers at Amersham Hospital in England．They trained different

kinds of dogs for the experiment．from people with other diseases and from healthy people．

Each dog was tested 8 times．In each test there were 7 samples for the dogs to smell．The dog

should signal the one from a bladder cancer patient by lying down next to it．Two cocker(一种猎犬）dogs were correct 56 percent of the time．But the scientists reported an average success rate of 41 percent．

The British Medical Journal published the research．In all, 36 bladder cancer patients and 108

other people took part．During training, all the dogs reportedly even identified（认出）a cancer in a person who had tested healthy before the study．Doctors found a growth on the person’s right kidney（肾）．

Carolyn Willis says dogs could help scientists identify the combined chemicals produced by

bladder cancer．That information could then be used to develop machines to test for the chemicals．The team also plans to use dogs to help identify markers for other kinds of cancer．

24. What’s the general idea of the text?

A．Dogs have a good sense of smell B．Dogs can help cure cancer

C．Dogs can smell cancer D．Dogs help perform experiments

25.According to the text, people who suffer bladder cancer_____

A．often have urine with unusual smell B．probably smoke cigarettes in their life

C．can easily make dogs lie down D．are likely to die within nine years

26.The underlined word “involved” in the text is closest in meaning to _____．

A．showed B．used C．proved D．preferred

27.What can we conclude from the last paragraph?

A．Dogs can only smell bladder cancer．

B．Dogs have a good knowledge of cancer．

C．Cancer doesn’t have any sign in the beginning．

D．Scientists might invent some equipment to test cancer．

C

Balzac was good at buying things at its lowest price. One day he wanted to buy a vase in a shop

window that was much more expensive than he could offer. Not being able to make the shopkeeper cut down its price very much, he left without further talking. Collecting a half dozen of his friends, he explained his wish to them and they worked a plan. The first would enter the shop and make an offer, lower than the marked price. Not getting the vase at his price, he would walk out. Shortly after