Just seven years ago,the Jarvik-7 artificial(人造的)heart was being cheered as the model of human creativeness. The sight of Barney Clark―alive and conscious after trading his diseased heart for a metal-and-plastic pump^convinced the press,the public and many doctors that the future had arrived. It hadn't. After monitoring production of the Jarvik-7, and reviewing its effects on the 150 or so patients (most of whom got the device as a temporary measure ) ,the U.S. Food and Drug

Administration concluded that the machine was doing more to endanger lives than to save them. Last week the agency cancelled its earlier approval, effectively banning the device.

The recall may hurt Symbion Inc.,maker of the Jarvik-7,but it won' t end the request for an artificial heart. One problem with the banned model is that the tubes connecting it to an external power source created a passage for infection. Inventors are now working on new devices that would be fully placed,along with a tiny power pack,in the patient's chest. The first sample products aren't expected for another 10 or 20 years. But some people are already worrying whether they'll work―and that America's overextended (开支过大的)health-care programs will lose a precious $2.5 billion to $ 5 billion a year providing them for a relatively few dying patients. If such expenditures(开支)cut into funding for more basic care,the net effect could actually be a decline in the nation,s health.

(   ) 8. According to the passage,the Jarvik-7 artificial proved to be         .

A.   a good life-saver

B.   a technical wonder

C.   an effective means to treat heart disease

D.   a technical failure

(   ) 9. From the passage we know that Symbion Inc.         .

A.  has been banned by the government from producing artificial hearts

B.  will review the effects of artificial hearts before designing new models

C.  may continue to work on new models

D.  can make new models of artificial hearts available on the market in 10 to 20 years (   ) 10. The new models of artificial hearts are expected .

A.  to have a working life of 10 or 20 years

B.  to be set fully in the patient' s chest

C.  to be equipped with an external power source

D.  to create a new passage for infection

(   ) 11. The underlined word "them" refers to ―.

A. doctors who treat heart diseases    B. makers of artificial hearts

C. America's health-care programs D. new models of artificial hearts

(   ) 12. Some people feel that         .

A.  artificial hearts are seldom effective

B.  the country is not spending enough money on artificial hearts

C.  the country should not spend so much money on artificial hearts

D.  America's health-care programs are not doing enough for the nation's health

One of the most striking findings of a recent questionnaire in the UK is that of the people inter?viewed,one in two believes that it is becoming more difficult to meet someone to start a family with.

Why are many people finding it increasingly difficult to start and keep close relationships? Does modern life really make it harder to fall in love? Or are we making it harder for ourselves?

It is certainly the case today that nowadays couples benefit in different ways from relationships. Women no longer rely upon partners for economic security or status. A man doesn,t expect his wife to be in sole (唯一的)charge of running his household and raising his children.

But perhaps the knowledge that we can live perfectly well without a partnership means that it takes much more to persuade people to abandon their independence.

In theory, finding a partner should be much simpler these days. Only a few generations ago,your choice of soul mate was restricted by geography, social convention and family tradition. Although it was never clear,many marriages were essentially arranged. Now those barriers have been broken down. You can approach a builder or a brain surgeon in any bar in any city on any given evening. When the world is your oyster(牡螈),you surely have a better chance of finding a pearl.

But it seems that the traditions have been replaced by an even tighter restriction:the limitation of choice. The expectations of partners are made greater to an unmanageable degree:good looks, impressive salary,kind to grandmother,and so on. There is no room for error in the first impression.

We think that a relationship can be perfect. If it isn't,it is intended to be thrown away. We work to protect ourselves against future heartache and don't put in the hard emotional labor needed to build a strong relationship. Twelve-hour work at the office makes relaxed after-hours dating difficult. The cost of housing and child-raising creates pressure to have a stable income and career before a life partnership.

(   ) 4. Nowadays,in a family, .

A. men are responsible for housework    B. couples share the burdens

C. men begin to depend on women    D. couples can't get along together

(   ) 5. People don't want to give up their independence because         .

A.  they think they can live happily alone

B.  they want to have more choices

C.  they can't bear arranged marriages

D.  they don't want to follow traditions

(   ) 6. People don,t bother to date because         .

A.   it needs faith to have a life partnership

B.   it takes them too much energy to work

C.   it requires luck to build a strong relationship

D.   it causes mental problems to find a life partner

(   ) 7. Which of the following can best describe the main idea of the passage?

A.   Independence is much more important than love.

B.   People should spend more money on marriage today.

C.   The expectations of partners and financial pressure may prevent a relationship.

D.   Even a perfect marriage can be given up for the sake of independence.

Most people know Alexander Graham Bell invented the telephone. But not many know about another talking device (equipment) he invented just four years later,in 1880. He called the device the photophone.

"Photophone" comes form the Greek words for "light" and "sound". The photophone did not use electricity to carry sound over wires between two people. That' s what a telephone does. Instead,

the photophone used a beam of sunlight traveling through the air. With his invention, Bell could actually transmit(传递)human speech on a beam of light. To do so,he spoke close to a thin mirror that was reflecting sunlight. The vibrations(颤动)of his voice caused the mirror to vibrate,and the vibrating mirror caused the light to vibrate. The vibrating light hit a light-sensitive cell in a receiver placed some distance away. The cell changed the light patterns into electrical signals. Earphones changed the signals back into sounds.

Bell believed that his idea of talking on a beam of light would prove to be important. He often called the photophone his greatest invention. Even though the photophone depended on a source of energy that was not constant一the sun―Bell wasn' t a bit discouraged. He felt sure that people would one day talk using beams of light.

Two much more recent developments made Bell' s dream come true. In 1960 ,a scientist built the laser. A laser produces a highly concentrated beam of light. Shortly afterward, other scientists developed a new kind of optical fiber. The optical fiber is a glass thread. The new fiber could carry light beams long distances―as far as several miles.

(   ) 1. According to Bell's own opinion,        is his greatest invention.

A. telephone    B. optical fiber C. photophone    D. laser

(   ) 2. What does "That" refer to in the underlined sentence?

A.  Using a beam of sunlight traveling through the air.

B.  Using electricity to carry sound over wires between two people.

C.  Transmitting human speech on a beam of light.

D.  Light and sound.

(   ) 3. Which statement is true about Bell,s invention of photophone?

A.   The photophone depends on a constant source of energy.

B.   The photophone is based on the invention of the telephone.

C.   Earphones are used to change light into sounds.

D.   The laser and the optical fiber are helpful for Bell' s invention.

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