Analysis of the composition of quicksand shows that there are four key ingredients—sand, obviously water, clay and salt. Together these materials form a structure resembling a house of cards, with large water-filled gaps between the sand particles, which are loosely glued in place by the clay. As long as it’s left alone, the structure remains stable. But as soon as it’s disturbed, by stepping on it, the clay changes from a jelly-like consistency to a runny liquid. The effect is the same as stirring a pot of yoghurt. Liquefying(溶解)the clay makes the quicksand about one million times runnier, and the whole house of cards comes tumbling down, with you inside it.

Very quickly, the sand sinks to the bottom and the water floats to the top. This is where the salt comes in. When there’s enough salt present, as soon as the clay particles liquefy, electrical charges make them begin to stick together to form bigger particles and these also settle with the sand. Quicksand is a mixture which looks like solid, but behaves more like a liquid.

Despite its murderous reputation, quicksand does not such people under and swallow them, although it can hold a person in firm grip. The human body is more buoyant(有浮力) in quicksand than in water, and sooner or later anyone trapped in it will float.

Unlike most liquids, quicksand’s viscosity, or “runniness” can suddenly change if it comes under pressure, for example under a human foot. The surface gives way and the victim quickly sinks in up to the knees, surrounded by an area of dirty things that turns semi-solid around its victim. Escaping from the quicksand’s grip(紧握) requires a large amount of force. Without something solid to pull at, people often find they are stuck fast. Pulling at one leg simply makes the other one sink further.

So how do you escape from quicksand’s control? Stay still and call for help. Staying still stops you sinking any further, until--with luck--help arrives on the scene. If no one appears and you need to draw yourself out, gently lie down on your back until your body is floating on the sand. Next, roll over onto your stomach and pull yourself forwards with your hands, so that you gradually “swim” towards firmer ground. It is a slow and dirty business, but it works.

This technique has one barrier: it goes against a very powerful human nature. Faced with danger in the open, nine out of ten stay on their feet so that they can run away, in which case it can worsen the situation.

1.Which ingredient of the quicksand make someone trapped in it stuck and stuck fast?

A. Sand B. Clay C. Water D. Salt

2.From the passage we can learn that ________

A. as long as you are strong enough, you can pull yourself up from quicksand on your own

B. clay glues sand particles loosely, which makes quicksand stable, unless it is disturbed

C. because anyone trapped in quicksand will float, there is little possibility of him dying

D. looking like solid ground, quicksand is actually liquid

3.If someone is trapped in quicksand, what should he do?

A. Remain calm and wave for help

B. Stand in quicksand and get ready to run away as quickly as possible

C. “Swimming” is one of the best choices he can use to escape

D. Once in quicksand, lie down on his stomach immediately and swim slowly to safety

4. What might be the best title of the passage?

A. A human killer--quicksand

B. How to escape from danger

C. An awful experience in quicksand

D. What to do if trapped in quicksand

完形填空,阅读下面短文,掌握其大意,从每题所给的A、B、C、D四个选项中,选出最佳选项,并在答题卡上将该项涂黑。

Mr. Jackson was blind from birth. He owned a fruit ____ on a very busy street. ____he was visually disabled, he ran his business pretty handsomely. He could see nothing and he could only ____ the things within his reach. ____, he was able to handle it and was content with everything he had.

One day his son came to him. He told Mr. Jackson in ____ that he read in the newspaper of a __46__ who could operate on his eyes and allow him to see. The father and the son traveled to the doctor and paid for the ____.

After the operation, the doctor asked Mr. Jackson, “What is the first thing you are ____ to see when I take the bandages off?” He replied, “I really want to see my beautiful ____ on my stand!”

The doctor and the son ____Mr. Jackson down to the busy street where his fruit stand had been located for so many years. The doctor ____ unwrapped the bandages ____ he could lay his eyes on the beautiful fruit! Mr. Jackson was so full of ____ that he could finally see his life’s work—taking care of his fruit! After a few hours of ____ his beautiful fruit stand, he looked down the street both ways and saw there were quite a few fruit stands in both directions. He looked ____ the street and saw many other fruit stands. He spent so much time looking at other people’s fruit stands and ____ the competition that soon his own business ____.

From Mr. Jackson’s failure, we should know that everyone is a ___ individual with different fingerprints, DNA and thinking. What we need to do is just be ourselves and ____everyone else to be who they are. Mind our own business and we should never be afraid of ____.

1.A. company B. stand C. store D. centre

2.A. Because B. as C. When D. Although

3.A. feel B. remember C. observe D. describe

4.A. However B. Therefore C. Otherwise D. Besides

5.A. pride B. doubt C. surprise D. excitement

6.A. nurse B. doctor C. chemist D. surprise

7.A. operation B. information C. medicine D. service

8.A. nervous B. lucky C. afraid D. eager

9.A. flowers B. fruit C. vegetable D. clothing

10.A. sent B. followed C. accompanied D. invited

11.A. carefully B. suddenly C. curiously D. firmly

12.A. in case B. so that C. even if D. if only

13.A. regret B. courage C. joy D. relief

14.A. selling B. judging C. enjoying D. making

15.A. above B. across C. within D. through

16.A. preparing for B. focusing on C. taking up D. worrying about

17.A. improved B. appeared C. expanded D. failed

18.A. unique B. reliable C. perfect D. simple

19.A. force B. require C. allow D. persuade

20.A. change B. difference C. competition D. disability

阅读下列短文,从每题所给的A、B、C、D四个选项中,选出最佳选项。

I was going to Paris, which I’d always wanted to see.But now I was frightened to travel alone.I arrived at the train station in Paris.I hadn’t spoken my college French for twenty years.On my first metro ride, I came across an incompetent(不胜任的)thief.I just stared at him, and he stopped his hand from my purse and disappeared into the crowd. Somewhere in this confusing city was my hotel hidden, but the directions suddenly weren’t easy to find. When I finally found the hotel, my heart was beating heavily, and I was sweating like a basketball player.I couldn’t stay.Could I? The wallpaper looked like it had been through a fire.The bathroom was downstairs, and the window looked out onto the brick wall of another building.Welcome to Paris.I sincerely wanted to die.I missed my friends.I was entering my third week away from home and my kids, and I had arrived in the most romantic city in the world, alone, lonely and frightened.

The most important thing I did in Paris happened at that moment.I knew that if I didn’t go out, right then, and find a place to have dinner, I would hide in this small room my entire time in Paris.I might never learn to enjoy the world as a single individual.So I went out.Evening in Paris was light and pleasant.I walked along a path, listening to birds sing, watching children float toy boats in a huge fountain.No one seemed to be in a hurry.Paris was beautiful.And I was here alone and suddenly not lonely.My sense of accomplishment overcoming my fear and weakness had left me feeling free.I wore out two pairs of shoes during my week’s stay in Paris.I did everything there was to do, and it was the greatest week of my European vacation.I returned home, becoming a believer in the power of traveling alone.Now when I meet difficulties I just say to myself, “If I can go to Paris, I can go anywhere.”

1.What happened on my first metro ride?

A. I came across a skillful thief.

B. I bravely caught a thief trying to steal

C. The thief successfully stole my purse

D. I scared away a thief trying to steal

2.The room in the hotel where I lived ______.

A. had just gone through a big fire

B. was in very poor conditions

C. had a good sight through the window

D. was very small and untidy

3.Which of the following is NOT true?

A. I was not lonely when I got to Paris.

B. I felt frightened travelling alone in Paris at first.

C. I then felt not lonely for the people around me in Paris.

D. I had a lot of walking during my stay in Paris.

4.The lifestyle of French people can be considered as ________.

A. hasty B. relaxed C. anxious D. aggressive

5.As to the writer, the power of traveling alone is _______.

A. the power of being independent

B. the power of feeling free

C. the power of becoming optimistic

D. the power of overcoming difficulties

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