Passage 1
Learning disabilities are very common. They affect perhaps 10 percent of all children. Four times as many boys as girls have learning disabilities.
Since about 1970, new research has helped brain scientists understand these problems better. Scientists now know there are many different kinds of learning disabilities and that they are caused by many different things. There is no longer any question that all learning disabilities result from differences in the way the brain is organized.
You cannot look at a child and tell if he or she has a learning disability. There is no outward sign of the disorder. So some researchers began looking at the brain itself to learn what might be wrong.
In one study researchers examined the brain of a learning-disabled person who had died in an accident. They found two unusual things. One involved cells in the left side of the brain, which control language. These cells normally are white. In the learning-disabled person, however, these cells were gray. The researchers also found that many of the nerve cells were not in a line the way they should have been. The nerve cells were mixed together.
The study was carried out under the guidance of Norman Geschwind, an early expert on learning disabilities. Doctor Geschwind proposed that learning disabilities resulted mainly from problems in the left side of the brain. He believed this side of the brain failed to develop normally. Probably, he said, nerve cells there did not connect as they should. So the brain was like an electrical device in which the wires were crossed.
Other researches did not examine brain tissue. Instead, they measured the brain's electrical activity and made a man of the electrical signals.
Frank Duffy experimented with his techniques at Children's Hospital Medical Center in Boston. Doctor Duffy said his research is evidence that reading disabilities involve damage to wide area of the brain, not just the left side.
Scientists found that the brain cells of a learning-disabled person differ from those of a normal person in ________.
文章第四段提到“控制语言的细胞的一般是白色的，而这个无学习能力者的细胞却是灰色的。而且许多细胞并没有按照它们应有的方式排成一条线，而是交织在一起”。由此可知正常人与没有学习能力的人的细胞差别在它们的颜色和组成方式，所以正确答案选D。
Which of the following is NOT mentioned in the passage?
文章倒数第三段提到“Doctor Geschwind proposed that learning disabilities resulted mainly from problems in the left side of the brain.”， Geschwind博士提出，学习障碍主要是由于大脑左侧的问题造成的。所以选项A表述不符合原文。B、C和D选项在下文都有提及，因此答案选A。
All of the following statements are true EXCEPT that ________.
文章第一段提到“They affect perhaps 10 percent of all children”，可知“学习障碍影响了大约10%的儿童”。而C选项说“学习障碍是一个常见的问题，影响了全部人口的10%”，与原文意思不符，故答案选 C。
Doctor Duffy believed that ________.
文章最后一段提到：Doctor Duffy said his research is evidence that reading disabilities involve damage to wide area of the brain, not just the left side。意思是：达菲博士说，他的研究表明，阅读障碍会对大脑的大面积区域造成损害，而不仅仅是左侧。B选项表述与原文相符，因此答案选B。
According to the passage we can conclude that further researches should be made ________.
文章主要描述的是有学习障碍的人的大脑发展和组织结构，所以未来应该有更多关于这些方面的研究，故正确答案选A。