An annoying problem for humans, who like to boast (夸耀) about all the distant planets and moons we have explored, is that we've never taken a good look right under our noses．The inside of the earth is relatively close but how can we get there?

The deepest oil well enters a mere six miles into the crust (地壳)  (the center of the earth is about 4,000 miles deeper)．Russian scientists dug the deepest hole in Siberia," but bottomed out at about 7.5 miles below the surface．The Mohole project, a U.S．plan in the 1950s, called for drilling a hole 25 miles down to the boundary be??tween the hard rocks of the crust and the soft mantle (地幔)．Sadly the project involved govern??ment supporting.

It gets harder and harder to drill deep into the earth because rocks get softer and softer． Hard but easily broken at the surface, rocks become plastic at depth, and the pressure caused by the weight of the overlaying crust — about 52,800 pounds per square inch at a depth of ten miles, makes further drilling impossible.

What little we know about the inside of the earth (like the fact that there' s a crust, a mantle, and a core) comes from indirect evidence, such as the analysis of earthquakes.

So maybe it' s time for a thorough new method to explore the earth's inside．Scientist David Stevenson says we should forget about drilling holes．Instead, we should open a crack (裂缝)． 

Stevenson suggests digging a crack about a half mile long, a yard wide, and a half mile deep (not with a shovel) but with an explosion on the scale of a nuclear bomb．Next, he'd pour a few hundred thousand tons of molten (融化的) iron into the crack, along with a robot．The iron, thicker than the surrounding crust, would move downward at about 16 feet per second, carrying the robot with it and opening the crack deeper and deeper．The iron mass would drop for about a week and 2,000 miles to the outer edge of the earth core, the robot sending out data to the sur??face.

Stevenson compares his idea to space explo??ration．"We're going somewhere we haven't been before," he says．"In all possibility, there will be surprises."

This idea can probably be put in．the drawer marked with Isn't Going To Happen．The robot would have to survive temperatures that would melt pretty much anything．But Stevenson's idea may inspire a new look at an old problem．Great things can come from what seems like impossible ideas.

Going inside the earth is ________ than going into space.

A．more interesting B．more possible    C．easier            D．more challenging

How deep have we gone into the earth until now?

A．6 miles．         B．4,000 miles． C．7.5 miles．        D．25 miles.

Which of the following is TRUE about David Stevenson's idea?

A．It is an inspiring but not practical idea now．

B．It is a practical proposal that has come into use now.

C．It is a good proposal that will soon be put into practice.

D．It is a false theory that cannot be carried out at all.

What might be the most suitable title for the text?

A．An Annoying Problem for Humans

B．To the Center of the Earth

C．The Mohole Project

D．David Stevenson' s Proposal

Six Americans are working on a new highway. But this highway won't have any traffic．It's an "ice highway" to the South Pole.

The team has just finished a second year of work on the 1,020-mile highway. "The road is the greatest single footprint of activity we've seen in the Antarctic (南极洲)," said Alan Hemmings, an Australian environmentalist.

The highway will provide a new way for supplies to be trekked (拉, 搬) across the earth on tractor-pulled sleds (雪橇). This method will use a lot less fuel than an aircraft, the current (当前的) way that scientists and supplies reach the Amundsen-Scott Base, a U.S. research station in the South Pole. The highway will also allow for equipment that is too big for planes to carry to be brought to Antarctica．Even with these benefits, there is one disadvantage—a round trip on the road will be 30 days, compared to a few hours by plane.

Making this 20-foot-wide road isn't easy, and it takes a lot of time. The crew (工作队) has been working on the road for two summers, when it's warmer and easier to work with the ice. It probably won't be completed until 2006.

Crevasses (裂缝), or cracks, in the land often make the construction difficult. Crevasses are kind of like pot holes that form when surface ice is stretched．This can be very dangerous, especially when the crevasses are hidden under a layer (层) of snow and can't be seen.

"Last year it took us three months to go three miles across a crevasse field, full of dangerous, hidden crevasses," said the project's manager, John Wright. Each year, more crevasses appear and they have to be filled with snow and ice so the road is safe for travel. The road will also be lined with green flags so travelers know where the safe surface is.

It will probably take ______ years to complete the ice highway.

       A．2     B．4      C．6      D．8

When it is finished, the highway will not be used for ______.

       A．giving supplies to the research station in the South Pole

       B．taking scientists to the South Pole

       C．taking travelers to a tour of Antarctic

       D．bringing huge equipment to Antarctic

How many miles can be covered at most each day if you take the ice highway to the South

Pole?

       A．30.    B．34.    C．68.    D．88.

Which of the following is true according to the passage?

       A．Other crevasses won’t appear if a crevasse has been filled.

       B．Many new crevasses will form after a crevasse has been filled.

       C．Travelers can drive their sleds on the ice highway freely.

       D．There will be less danger if the crevasses are covered by snow.

Thirteen vehicles lined up last March to race across the Mojave Desert , seeking a million in prize money . To win , they had to finish the 142-mile race in less than 10 hours . Teams and watchers knew there might be no winner at all , because these vehicles were missinge a key part drivers .

DARPA , the Defense Advanced Research Projects Agency , organized the race as part of a push to develop robotic vehicles for future battlefields . But the Grand Challenge , as it was called , just proved how difficult it is to get a car to speed across an unfamiliar desert without human guidance . One had its brake lock up in the starting area . Another began by throwing itself onto a wall . Another got tied up by bushes near the road after 1.9 miles .

One turned upside down . One took off in entirely the wrong direction and had to be disabled by remote (远距离的) control . One went a little more than a mile and rushed into a fence ; another managed to go for six miles but stuck on a rock . The “winner,” if there was any , reached 7.8 miles before it ran into a long , narrow hole , and the front wheels caught on fire .

“You get a lot of respect for natural abilities of the living things,” says Reinhold Behringer , who helped design two of the car-size vehicles for a company called Sci-Autonics . “Even ants (蚂蚁) can do all these tasks effortlessly . It’s very hard for us to put these abilities into our machines .”

The robotic vehicles , though with necessary modern equipment such as advanced computers and GPS guidance , had trouble figuring out fast enough the blocks ahead that a two-year-old human recognizes immediately , Sure , that very young child, who has just only learned to walk , may not think to wipe apple juice off her face , but she already knows that when there’s a cookie in the kitchen she has to climb up the table , and that when she gets to the cookie it will taste good . She is more advanced , even months old , than any machine humans have designed .

67．Watchers doubted if any of the vehicles could finish the race because        .

       A．they did not have any human guidance

       B．the road was not familiar to the drivers

       C．the distance was too long for the vehicles

       D．the prize money was unattractive to the drivers

68．DARPA organized the race in order to          .

       A．raise money for producing more robotic vehicles

       B．push the development of vehicle industry

       C．train more people to drive in the desert

       D．improve the vehicles for future wars

69．From the passage we know “robotic vehicles” are a kind of machines that          .

       A．can do effortlessly whatever tasks living thing can

       B．can take part in a race across 142 miles with a time limit

       C．can show off their ability to turn themselves upside down

       D．can move from place to place without being driven by human beings

70．In the race , the greatest distance one robotic vehicle covered was          .

       A．about eight miles                                 B．six miles

       C．almost two miles                                 D．about one mile

71．In the last paragraph , the writer implies that there is a long way to go          .

       A．for a robotic vehicle to finish a 142-mile race without any difficulties

       B．for a little child who has just learned to walk to reach the cookie on the table

       C．for a robotic vehicle to deal with a simple problem that a little child can solve

       D．for a little child to understand the importance of wiping apple juice off its face

Thirteen vehicles lined up last March to race across the Mojave Desert, seeking a million in prize money. To win, they had to finish the 142-mile race in less than 10 hours. Teams and watchers knew there might be no winner at all, because these vehicles were missing a key part －drivers.

DARPA, the Defense Advanced Research Projects Agency, organized the race as part of a push to develop robotic vehicles for future battlefields. But the Grand Challenge, as it was called, just proved how difficult it is to get a car to speed across an unfamiliar desert without human guidance. One had its brake lock up in the starting area. Another began by throwing itself onto a wall. Another got tied up by bushes near the road after 1.9 miles.

One turned upside down. One took off in entirely the wrong direction and had to be disabled by remote (远距离的) control. One went a little more than a mile and rushed into a fence; another managed to go for six miles but stuck on a rock. The “winner,” if there was any, reached 7.8 miles before it ran into a long, narrow hole, and the front wheels caught on fire.

“You get a lot of respect for natural abilities of the living things,” says Reinhold Behringer, who helped design two of the car-size vehicles for a company called Sci-Autonics. “Even ants (蚂蚁) can do all these tasks effortlessly . It’s very hard for us to put these abilities into our machines.”

The robotic vehicles, though with necessary modern equipment such as advanced computers and GPS guidance, had trouble figuring out fast enough the blocks ahead that a two-year-old human recognizes immediately, Sure, that very young child, who has just only learned to walk, may not think to wipe apple juice off her face, but she already knows that when there’s a cookie in the kitchen she has to climb up the table, and that when she gets to the cookie it will taste good. She is more advanced, even months old, than any machine humans have designed.

Watchers doubted if any of the vehicles could finish the race because        .

A．they did not have any human guidance

B．the road was not familiar to the drivers

C．the distance was too long for the vehicles

D．the prize money was unattractive to the drivers

DARPA organized the race in order to         .

A．raise money for producing more robotic vehicles

B．push the development of vehicle industry

C．train more people to drive in the desert

D．improve the vehicles for future wars

From the passage we know “robotic vehicles” are a kind of machines that         .

A．can do effortlessly whatever tasks living thing can

B．can take part in a race across 142 miles with a time limit

C．can show off their ability to turn themselves upside down

D．can move from place to place without being driven by human beings

In the race, the greatest distance one robotic vehicle covered was          .

A．about eight miles    B．six miles

C．almost two miles     D．about one mile

In the last paragraph, the writer implies that there is a long way to go         .

A．for a robotic vehicle to finish a 142-mile race without any difficulties

B．for a little child who has just learned to walk to reach the cookie on the table

C．for a robotic vehicle to deal with a simple problem that a little child can solve

D．for a little child to understand the importance of wiping apple juice off its face

You can't escape the message that smoking is bad for you.But what if one or both of your parents smoke?You might be worried about their health,sick of smelling the smoke,or even a little embarrassed(尴尬的) by it.You can't order your mom or dad to stop smoking ,but you can encourage them to quit.There are lots of good reasons.Here are some you can mention:

*Smoking will hurt their health.

*Smoking creates secondhand smoke,which you don't like .

*Smoking will make it hard for them to keep up with you because they might run out of breath easily.

If you think it will help,you could print out articles like this one to give it to your mom or dad. But what if your parent gets angry with you for bringing up the topic of smoking?People don't like to be reminded that they are doing something unhealthy,so it's possible that your parents will be insulted or angry,especially if they're worried they won't be able to quit.Maybe they have tried before and failed.

Remember to be kind and respectful when you discuss smoking with your mom or dad. Also rememeber that it is difficult to quit.Some people try several times before they're able to quit for good. Instead of yelling at the them,tell them that you love them and want them to enjoy many healthy years ahead. In time,your mom or dad may realize you are right about smoking .And if they do agree to stop smoking,be their biggest supporter.Ask if there's anything you can do to help them when they feel the urge to smoke.Maybe you could go for a walk,do a puzzle,or listen to music together.As they reach milestones,such as a month without smoking,be sure to celebrate the achievement.Way to go,mom!Way to go,dad!

1. In the first paragraph,the author intended to tell us______.

A.the reasons you have for your parents' giving up smoking

B.the great damage smoking can cause to secondhand smokers

C.most smokers are includable and stubborn

D.smoking does harm to smoker's health

2. If you bring up the topic of smoking directly,_________.

A.the smokers will accept your advice willingly 

B.the smokers may become very annoyed at once

C.the smokers will take your words into account  

D.the smokers will put you in an embarrassing situation

3.The underlined word "milestones" in the first paragraph means________.

A.stones which are miles away    

B.agreements signed by both sides

C.practical tools for stopping smoking 

D.achievements gained with great efforts

4.The author wrote the text for_______.

A.school teachers      B.health experts   

C.sons and daughters   D.medical scientists