It is best to avoid using startling statements or questions in openers to an oral presentation.

Passage 1 Left-handers and Right-handers Imagine you are a left-hander. Suddenly everything in the world is changed. The door locks are on the wrong side of doors. The shift-gears in your car is in the wrong place. Handles on tin openers are on the wrong side and turn the wrong way. Twenty-five million Americans wake up every day in just such a sorry situation. They are one in ten of us who are left-handed and must face the world designed for the right-handed majority. Why we are left or right-handed remains one of the greatest unsolved mysteries of science. We know that nearly two out of three lefties are men and that left-handedness runs in families. According to one study almost half of the children of two left-handed parents will be left-handed. The Scots-Irish family Kerr produced so many left-handers that in 1470 the family built its house stairway with a reverse twist. On the other hand, heredity alone cannot explain lefties. 84 percent of them are born of two right-handed parents. And in 12 percent of twins, one will be right-handed, the other left. Perhaps the greatest puzzle of all is not why some people are left-handed, but rather why so few are. In fact, almost equal numbers of individuals will favor either the right or the left. However, scientists are trying to set things right and they are beginning to study the many ways left-handers differ from right-handers by considering how their brains work. 1. Based on the passage, we know that of Americans are left-handers. A) 25% B) 10% C) 16% D) 12% 2. We can say from the passage that . A) scientists have found out how left-handers' brains work B) people prefer to be right-handers C) left-handers lead a life in somewhat inconvenient way D) no other families have so many left-handers as the Kerrs 3. Which of the following statements is true according to the passage? A) Half of the left-handers are men. B) Most of the twins are left-handers. C) There are more male left-handers than female ones. D) The greater part of left-handers have left-handed parents 4. Why so few people are left-handers . A) has nothing to do with heredity B) is not known by scientists C) puzzles left-handed people D) is no concern of common people 5. The word "reverse" (Last Line, Para.3) most probably means . A) contrary B) different C) ridiculous D) mysterious New Words and Expressions heredity 遗传 twist 弯曲，曲折处

Questions 30 to 34 are based on the following passage. What do Leonardo da Vinci (达芬奇) and Albert Einstein have in common? They were both left-handed, along with other famous people including Pablo Picasso (毕加索). In fact, an estimated 11 percent of Americans and Europeans are left-handed. Most people around the world are right-handed. This fact also seems to have held true throughout history. In 1977, scientists studied works of art made at various time in history starting with cave drawings from 15,000 B.C. and ending with paintings from the 1950s. Most of the people shown in these works of art are right-handed, so scientists guessed that right-handedness has always been common. Many researchers claim to have found relationships between left-handedness and various physical and mental characteristics, such as blond hair, blue eyes, vegetarianism, and sleep difficulties. Other studies have found a higher-than-normal level of left-handed people in certain occupations, including professional baseball and tennis players, architects, lawyers, as well as prisoners. However, some of these connections are very weak, and others haven’t been proven. What makes a person become right-handed rather than left-handed? As yet, no one really knows for sure. One simple idea suggests that people normally get right-handedness from their parents. Studies have found that two right-handed parents have only 9.5 percent chance of having a left-handed child, while two left-handed parents have a 26 percent chance of having a left-handed child. Another common theory is that left-handed people suffer mild brain damage during their birth. Whatever the reasons behind it, people’s attitudes toward left-handedness have changed a lot over the years. Statistics show that although 13 percent of young people (10-12 years old) are left-handed, only 6 percent of the elderly are left-handed. Left-handed children used to be punished until they began using their right hand like other children, but today people who are left-handed are no longer looked down upon nor are they considered abnormal. For most people today either case is perfectly acceptable. There are even a number of shops now that specialize in selling products designed for left-handed people, such as left-handed scissors, can openers, guitars, and even a left-handed camera. Don’t you think it’s wonderful? 30. From studying works of art, scientists have learned that ________.