Do you know how it is when you see someone yawn and you start yawning too? Or how hard it is to be among people laughing and not laugh yourself? Well, apparently it's because we have mirror neurons(神经元)in our brains.

Put simply, the existence of mirror neurons suggests that every time we see someone else do something, our brains imitate(模仿)it, whether or not we actually perform the same action. This explains a great deal about how we learn to smile, talk, walk, dance or play sports. But the idea goes further: mirror neurons not only appear to explain physical actions, they also tell us that there is a biological basis for the way we understand other people.

Mirror neurons can undoubtedly be found all over our brains, but especially in the areas which relate to our ability to use languages, and to understand how other people feel. Researchers have found that mirror neurons relate strongly to language. A group of researchers discovered that if they gave people sentences to listen to(for example：“The hand took hold of the ball”), the same mirror neurons were triggered as when the action was actually performed(in this example, actually taking hold of a ball)．

Any problems with mirror neurons may well result in problems with behavior. Much research suggests that people with social and behavioral problems have mirror neurons which are not fully functioning. However, it is not yet known exactly how these discoveries might help find treatments for social disorders.

Research into mirror neurons seems to provide us with ever more information concerning how humans behave and interact(互动)．Indeed, it may turn out to be the equivalent(相等物)for neuroscience of what Einstein's theory of relativity was for physics. And the next time you feel the urge to cough in the cinema when someone else does—well, perhaps you'll understand why.

20．Mirror neurons can explain ________．

A．why we cry when we are hurt

B．why we cough when we suffer from a cold

C．why we smile when we see someone else smile

D．why we yawn when we see someone else stay up late

21．The underlined word “triggered” in the third paragraph probably means “________”．

A．set off  B．cut off

C．built up  D．broken up

22．We can learn from the passage that mirror neurons ________．

A．relate to human behavior and interaction

B．control human physical actions and feelings

C．result in bad behavior and social disorders

D．determine our knowledge and language abilities

23．What is the passage mainly about?

A．Ways to find mirror neurons.

B．Problems of mirror neurons.

C．Existence of mirror neurons.

D．Functions of mirror neurons.

Mr. Jones, of the Manor Farm, had locked the hen­houses for the night, but was too drunk to remember to shut the door.With the ring of light from his lantern dancing from side to side, he drew himself a last glass of beer and made his way up to bed.

As soon as the light in the bedroom went out, there was a big noise all through the farm buildings. Word had gone round during the day that old Major, the prize Middle White pig, had had a strange dream on the previous night and wished to communicate it to the other animals. It had been agreed that they should all meet in the big barn(谷仓) as soon as Mr.Jones was safely out of the way.

At one end of the big barn, Major lay on his bed of straw comfortably. He was twelve years old and had lately grown rather heavy, but he was still a nice­looking pig, with a wise and easy­going appearance. Before long the other animals began to arrive and make themselves comfortable after their different fashions. First came the three dogs, Bluebell, Jessie, and Pincher, and then the pigs, who settled down in the straw immediately beside Major. The two cart­horses, Boxer and Clover, came in together, walking very slowly and setting down their vast hairy hoofs(蹄子) with great care for fear that there should be some small animals hidden in the straw. Clover was a motherly big horse approaching middle life, who had never quite got her figure back after her fourth kid.

Boxer was an enormous beast, nearly eighteen hands high, and as strong as any two ordinary horses put together. A white stripe down his nose gave him a somewhat stupid appearance, and in fact he was not of first­rate intelligence, but he was well respected for his steadiness of character and extraordinary abilities. After the horses came Benjamin, the donkey, Benjamin got angry easily. He seldom talked, and when he did, it was usually to make all such remarks—for instance, he would say that God had given him a tail to keep the flies off, but that he would rather have had no tail and no flies. Alone among the animals on the farm he never laughed. If asked why, he would say that he saw nothing to laugh at.

16．All the animals came to the barn to ________．

A．vote for a farm master

B．listen to Major's strange dream

C．discuss how to win a prize

D．share how to drive Mr. Jones away

17．According to the passage, Clover was ________．

A．considerate and in good shape

B．old­aged and out of shape

C．a fat horse with a gentle heart

D．a pretty horse with a nice character

18．What earned Boxer high respect?

A．His strong build and great wisdom.

B．His calm character and great powers of work.

C．His good temper and strong build.

D．His steady character and quick mind.

19．Which remark could be to Benjamin's taste?

A．Life is like a box of sweets.

B．Life is an interesting journey.

C．Life is a battle.

D．There is nothing exciting in life.

She is still new in________field of acting and it will take her a long time to master tricks of________trade.

A．a; the  B．the; /

C．the; the  D．a; /

—Are you________ me of lying to the headmaster?

—I'm sure you did.

A．accusing  B．scolding

C．reminding  D．telling

The customers complained that not only________high, but he didn't do a good repair job.

A．he charged  B．was he charged

C．did he charge  D．he was charged

—You________have finished your composition.

—I had meant to，but before I could，the bell rang and I had to hand in my test paper.

A．were supposed to  B．were able to

C．had to  D．were determined to

She wishes her parents to ________ of her boyfriend, for she loves him badly.

A．accept  B．admit  C．accuse  D．approve

 Leave your key with your neighbor ________ you lock yourself out one day.

A．as long as  B．even though

C．in case  D．as if

The average Facebook user in the United States has 245 friends, according to a study ________ in February.

A．publishing  B．published

C．publish  D．to publish

—How do you know so much about what's going on in the countryside?

—I've got a friend there who keeps me ________．

A．informing  B．to be informed

C．informed  D．being informed