Text 3

　　Efforts could potentially avoid at least some of the psychopathy (mental illness) that underlies school shootings, since medicine now can help even the most severely ill. And they would also benefit the many young people struggling with far less extreme brain disorders.

　　The U.S. Secret Service, which studies “targeted violence”, provides insight on the urgency of the need in its 2002 “Safe School Initiative” report: School attacks, instead of being the random impulsive acts of noisy and cruel fellows, are well-planned events mostly carried out by a single student—who is not evil but mentally ill. Except for being male, the 41 attackers studied fit no profile of family background，race，ethnicity，or even academic performance. Many were A and B students. Few had a history of violent or criminal behavior. But their thoughts were of violence, and their behavior was often intimidating. They frequently expressed violent themes in their writings, in one instance portraying killing and suicide as solutions to feelings of despair. The criminals often had telegraphed to other students and teachers their depression or desperation and either talked about or had attempted suicide. Feelings of persecution by others were common and led to growing resentment and anger.

　　Psychiatrists and psychologists recognize that these are red flags demanding medical intervention. Yet one of most striking findings in the report was that the vast majority of these students never had a mental-health evaluation. No wonder only 17 percent were diagnosed with a psychiatric illness—it wasn’t looked for. That alone points to a huge mental health gap: If the distress of these students didn’t trigger medical attention, it’s unlikely that less severe struggles that are seen in as many as 15 to 20 percent of other students will do so.

　　Only recently have we learned that these are neurodevelopmental disorders whose early signs might well be picked up in routine podiatric screening. For example, a classic behavior in a child that can precede psychosis later in 1ife is speaking to almost no one, even family, says Nasrallah.

　　Genes are known to confer vulnerability, but equally important is the environment. Stress or great disappointment can aggravate symptoms; Connecting with an adult in an ongoing relationship can do the opposite. Interventions like social-skills training combined with talk therapy and targeted medication can make a huge difference. Early treatment can lessen the frequency and intensity of psychotic episodes, leaving many patients with only the mildest of symptoms. And the younger the brain, the more malleable is. The ultimate goal is to not only modify evaluation of disease but keep it from arising in the first place. This is achievable, and the path to get there is becoming clear.

　　51. According to the US Secret Service, school attacks are characterized as .

　　[A] reactive

　　[B] revengeful

　　[C] plotted

　　[D] impulsive

　　52. One common characteristic of school attackers is that .

　　[A] they exhibit bad academic performances

　　[B] they have violent thoughts and intimidating behavior

　　[C] they regard homicide and suicide as ways of tackling despair

　　[D] they have records of violence and crimes

　　53. Which of the following is true according to Paragraph 3?

　　[A] There is a huge gap between human mentality.

　　[B] The school attackers have never had any mental health evaluation.

　　[C] Medical attention should be paid to the distress of school attackers.

　　[D] The findings of the report astonished psychiatrists and psychologists.

　　54. The word “malleable” (Line 5, Paragraph 5) is closest in meaning to .

　　[A] miserable

　　[B] adaptable

　　[C] vulnerab1e

　　[D] feeble

　　55. What can we conclude from the last paragraph?

　　[A] Both genes and environment should be improved to tackle brain disorders.

　　[B] Prevention is by far more important than treatment.

　　[C] Mental disorders are curable, and the earlier the better.

　　[D] Early treatment can reduce the sufferings and terminate all the symptoms.

　　Text 4

　　Scientists have known since 1952 that DNA is the basic stuff of heredity. They’ve known its chemical structure since 1953. They know that human DNA acts like a biological computer program some 3 billion bits long that spells out the instructions for making proteins, the basic building blocks of life.

　　But everything the genetic engineers have accomplished during the past half-century is just a preamble to the work that Collins and Anderson and legions of colleagues are doing now. Collins leads the Human Genome Project, a 15-year effort to draw the first detailed map of every nook and cranny of gene in human DNA. Anderson, who pioneered the first successful human gene-therapy operations, is leading the campaign to put information about DNA to use as quickly as possible in the treatment and prevention of human diseases.

　　What they and other researchers are plotting is nothing less than a biomedical revolution. Like Silicon Valley pirates reverse-engineering a computer chip to steal a competitor’s secrets, genetic engineers are decoding life's molecular secrets and trying to use that knowledge to reverse the natural course of disease. DNA in their hands has become both a blueprint and a drug, a pharmacological substance of extraordinary potency that can treat not just symptoms or the diseases that cause them but also the imperfections in DNA that make people susceptible to a disease.

　　And that’s just the beginning. For all the fevered work being done, however, science is still far away from the Brave New World vision of engineering a perfect human—or even a perfect tomato. Much more research is needed before gene therapy becomes commonplace, and many diseases will take decades to conquer, if they can be conquered at all.

　　In the short run, the most practical way to use the new technology will be in genetic screening. Doctors will be able to detect all sorts of flaws in DNA long before they can be fixed. In some cases the knowledge may lead to treatments that delay the onset of the disease or soften its effects. Someone with a genetic predisposition to heart disease, for example, could follow a low-fat diet. And if scientists determine that a vital protein is missing because the gene that was supposed to make it is defective, they might be able to give the patient an artificial version of the protein. But in other instances, almost nothing can be done to stop the ravages brought on by genetic mutations.

　　56. It can be inferred from the text that Collins and Anderson and legions of colleagues _____.

　　[A] know that human DNA acts like a biological computer program

　　[B] have found the basic building blocks of life

　　[C] have accomplished some genetic discovery during the past half-century

　　[D] are making a breakthrough in DNA

　　57. Collins and Anderson are cited in the text to indicate all the following EXCEPT that ______.

　　[A] gene-therapy now is already generally used to the treatment and prevention of human diseases

　　[B] human gene-therapy operations may be applied to the patients

　　[C] time-consuming effort is needed to accomplish the detailed map of in human DNA

　　[D] information about DNA may be used in the treatment and prevention of human diseases

　　58. The word “pirate” (line 2, paragraph 3) most probably means______.

　　[A] one who robs at sea or plunders the land from the sea

　　[B] one who makes use of or reproduces the work of another without authorization

　　[C] to take (something) by piracy

　　[D] to make use of or reproduce (another’s work) without authorization

　　59. We can draw a conclusion from the text that_____.

　　[A] engineering a perfect human is not feasible for the time being

　　[B] it’s impossible for scientists to engineer a perfect tomato

　　[C] many diseases will never be conquered by human beings

　　[D] doctors will be able to cure all sorts of flaws in DNA in the long run

　　60. The best title for the text may be ______.

　　[A] DNA and Heredity

　　[B] The Genetic Revolution

　　[C] A Biomedical Revolution

　　[D] How to Apply Genetic Technology