Few things say “forget I'm here” quite so eloquently as the pose of the shy—the averted gaze, the hunched shoulders, the body pivoted away from the crowd. Shyness is a state that can be painful to watch, worse to experience and, in survival terms at least, awfully hard to explain. In a species as hungry for social interaction as ours, a trait that causes some individuals to shrink from the group ought to have been snuffed out pretty early on. Yet shyness is commonplace. “I think of shyness as one end of the normal range of human temperament,” says professor of pediatrics William Gardner of Ohio State University.

　　But normal for the scientist feels decidedly less so for the painfully shy struggling merely to get by, and that's got a lot of researchers looking into the phenomenon. What determines who's going to be shy and who's not? What can be done to treat the problem? Just as important, is it a problem at all? Are there canny advantages to being socially averse that the extroverts among us never see? With the help of behavioral studies, brain scans and even genetic tests, researchers are at last answering some of those questions, coming to understand what a complex, and in some ways favorable, state shyness can be.

　　For all the things shyness is, there are a number of things it's not. For one, it's not simple introversion. If you stay home on a Friday night just because you prefer a good book to a loud party, you're not necessarily shy—not unless the prospect of the party makes you so anxious that what you're really doing is avoiding it. “Shyness is a greater than normal tension or uncertainty when we're with strangers,” says psychologist Jerome Kagan of Harvard University. “Shy people are more likely to be introverts, but introverts are not all shy.”

　　Still, even by that definition, there are plenty of shy people to go around. More than 30% of us may qualify as shy, says Kagan, a remarkably high number for a condition many folks don't even admit to. There are a lot of reasons we may be so keyed up. One of them, new research suggests, is that we may simply be confused.

　　In a study published early this year, Dr. Marco Battaglia of San Raffaele University in Milan, Italy, recruited 49 third-and fourth-grade children and administered questionnaires to rank them along a commonly accepted shyness scale. He showed each child a series of pictures of faces exhibiting joy, anger or no emotion at all and asked them to identify the expressions. The children who scored high on the shyness meter, it turned out, had a consistently hard time deciphering the neutral and the angry faces.

　　36. In paragraph 2, the writer intends to _______________

　　[A] introduce paragraph 3.

　　[B] illustrate the questions scientists are asking and how they can find answers to them.

　　[C] contrast the ideas raised in paragraph 1.

　　[D] show us the writer\'s field of interest and expertise.

　　37. Why is it considered strange that there are so many shy people?

　　[A] Because it is considered by psychologists to be an undesirable trait.

　　[B] Because it is not a trait associated with social animals.

　　[C] Because our ancestors were not shy, so we should be like them.

　　[D] Because shy people could not have survived in early human society.

　　38. Which of the following people would psychologists certainly consider to be shy?

　　[A] A person who prefers to study alone rather than spend time with friends.

　　[B] A person who is afraid to talk to an attractive person of the opposite sex.

　　[C] A person who isn't good at introducing themselves to new people.

　　[D] A person who feels exceptionally nervous when around unfamiliar people.

　　39. It is suggested that shy people might be confused because ________________

　　[A] they misinterpret other people's facial expressions.

　　[B] they have problems recognising certain facial expressions.

　　[C] they are extremely introverted.

　　[D] they are unable to admit to being shy.

　　40. Which of the following would best replace the word “canny” used in paragraph 2?

　　[A] clever. [B] distinct.

　　[C] unknown. [D] surprising.