题目内容

He feels relaxed and even begins to whistle because ________ of the distance ________ covered.
[     ]
A. three fifth; were
B. three fifth; was
C. three fifths; have been
D. three fifths; has been
D
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Microwaves may be great at warming up food, but what about warming people?

Using microwaves to directly heat owners of a room would save much of the energy wasted by heating walls and furniture. And despite popular ideas about microwaves, this technique would be safe, according to Charles R. Burlier of the Microwave Research Center in Marlborough, New Hampshire. Low-power microwaves only penetrate (贯穿) the skin (low-power microwave penetration in a ham is about 0.2 inches, for example) and with no negative effects.

To test this idea, Buffler subjected himself to microwaves in a special room using a standard 500-watt, 2459 MHz magnetron (磁控管). He found that a person will start to feel warmth at about 20 milliwatts per square centimeter (mw. / sq. cm. ) ; a satisfactory feeling of warmth occurs between 35 and 50mw. / sq. cm. By comparison, a person standing in noonday summer sun feels the amount of 85 mw. / sq. cm. And a frozen meat pie in your microwave oven receives about 1000 mw. / sq. cm.

In houses of the future, each room could be provided with its own magnetron, says Buffler. When you stepped into the living room, for example, a motion detector (运动感应器)would turn on the magnetron, filling the room with low-power microwaves. In the same way that a microwave oven heats up a hamburger, but not the plate it’s on, you would feel warmth from the microwaves without changing the temperature of your coffee table. (You could, however, make your favorite easy chair even more comfortable by treating it with a radiation-absorbing chemical.)

While it might be some time before homeowners are comfortable enough with the idea to set up whole-body microwave heaters in houses, Buffler says microwaves may attract livestock(家畜) farmers. Lambs that are born outdoors in winter, for example, are frequently lost to cold. Microwaves could warm the lambs safely and quickly.

1.Which of the following can tell the main idea of the passage?

A．A new heating system.                   B．A new microwave oven.

C．A popular technique.                     D．The magnetron.

2.According to Paragraph 2, which of the following does not describe the characteristics of a microwave heater?

A．It directly heats people in a room.

B．It heats walls and furniture in a room.

C．It is safe.

D．It saves energy.

3.The test conducted by Buffler shows that when a person feels comfortable warmth, he receives about ________________.

A．20 mw. / sq. cm.    B．40 mw. / sq. cm.     C．60 mw. / sq. cm.     D．85 mw. / sq. cm.

4.According to Paragraph 4, which of the following fills the room with low-power microwaves?

A．The magnetron.                        B．The motion detector.

C．The microwave oven.                    D．The radiation-absorbing chemical.

5.Which of the following statements about microwave heaters would Buffler most probably agree with?

A．Microwave heaters will soon be widely used by homeowners.

B．Microwave heaters sometimes make people feel uncomfortable.

C．Perhaps microwave heaters will be first used by livestock farmers, who wish to protect their lambs in winter.

D．Microwave heaters cannot be accepted by the public because they are somewhat unsafe.

 

It's 10:30 pm, and 11-year-old Brandon Blanco is sound asleep at home. Suddenly, a loud noise wakes him up. Naturally, Brandon reaches for his cell phone. The message becomes clear: "R U awake?"

Brandon' s use of technology doesn' t stop there. He also has a computer, a TV and three video-game consoles (控制台 ) in his room. With so many choices, it' s no surprise that when he isn' t at school, he spends nearly every waking minute using one or more of these devices

Brandon is hardly alone. According to a recent study by the Kaiser Family Foundation, kids aged 8 to18 are spending more time than ever before using electronic devices. How much time? More than seven and a half hours a day on average, the study found.

The jump is the result of a huge explosion in mobile devices, says Victoria Rideout, the lead author of the study. Today, nearly seven out of ten kids have cell phones. Just five years ago, it was four out of ten.

Often, kids multitask, or use more than one device at a time. " If you’ve got a chance to do something on your computer and take a phone call and have the TV on in the background, why not?" media expert Cheryl Olson says.

Most experts agree technology has much to offer kids. But some worry the kids could be missing out on other activities like playing outside or hanging out with friends. " It' s a matter of balance," says Olson." You’ve got to work on it. "

Multitasking while doing homework is another concern. Some kids listen to music, watch TV or use the phone while doing their homework. "It' s important to make sure that you can stop and concentrate on one thing deeply, " says Rideout.

With new and exciting devices hitting stores every year, keeping technology use in check is more important than ever. " Kids should try," adds Rideout. " But parents might have to step in sometimes. "

1.Why do children spend more time in using electronic devices?

A．Because more electronic devices are available to them.

B．Because electronic devices are more exciting than before.

C．Because they have less other activities.

D．Because they have less homework to do.

2.It is known from the passage that  ____.

A．Brandon Blanco feels very annoyed about his late-night text

B．the teenagers using mobile devices have increased by 30% in the past five years

C．Cheryl Olson is not surprised about kids' increasing use of mobile devices

D．most experts think teenagers should not use electronic devices for their studies

3.Which of the following is an example of multitasking according to the passage?

A．Watching TV while using the computer.

B．Talking on the phone while staying with others.

C．Playing video games on the Internet.

D．Listening to music while relaxing.

4.According to the passage, Victoria Rideout would probably agree that ____.

A．kids should do homework while surfing the Internet

B．kids should do homework in a place without disturbance

C．kids should spend more time on homework

D．kids should have more homework than before

 

根据首字母填空（共5 小题；每小题1分，满分5分）

71. He ran across to the o________  side of the street.

72. We Chinese have friends t    _____ the world.

73. They drew simple pictures or signs to r_________ things and ideas, and also the sounds of their language.

74. His situation is very c___________ , so no one is willing to get involved.

75. He feels c___________ of passing the examination.

 

第Ⅱ卷(共35分)

第四部分：(共两节，满分35分)

第一节：根据首字母填空（共5 小题；每小题1分，满分5分）

71. He ran across to the o________  side of the street.

72. We Chinese have friends t    _____ the world.

73. They drew simple pictures or signs to r_________ things and ideas, and also the sounds of their language.

74. His situation is very c___________ , so no one is willing to get involved.

75. He feels c___________ of passing the examination.

根据首字母填空（共5 小题；每小题1分，满分5分）

71. He ran across to the o________  side of the street.

72. We Chinese have friends t    _____ the world.

73. They drew simple pictures or signs to r_________ things and ideas, and also the sounds of their language.

74. His situation is very c___________ , so no one is willing to get involved.

75. He feels c___________ of passing the examination.

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