题目内容
2. The study raises the possibilitydieting is bad for your health.
2. that
Task III. Read the text and decide whether the following statements are True (T) or False (F)
1. Li Daiyu,her cousin and Danny Lin chose to take the train to cross Canada from west to
east.
2. They could see more great scenery if they travelled by plane.
3. The distance from west to east in Canada is 5 ,500 km.
4. In Vancouver the population is growing slowly because many people are moving away.
5. It is common for people to see some wild animals in the Rocky Mountains.
6. The girls were surprised to see that Canada is so empty.
7. It is impossible for ocean ships to sail up the Great Lakes.
8. In the world,Canada is the country that has the most fresh water.
The mystery of why humans are the only animals to have chins (下巴) may have been solved by scientists who suggest that it is connected to the invention of cooking.
A paper from the University of Florida tries to explain exactly why humans 一 unlike all other primates (灵长目动物) 一have chins.
A team led by Dr James Pampush collected information from more than 100 kinds of primate and compared it with historical information. Computer modelling found how the chin developed.
Random genetic change(随机的基因变化)was ruled out because the chin developed 77 times faster than the average genetic change. And the study finds no evidence that it -served a useful purpose. The research,published in the Journal of Human Evolution,suggests the chin is a by-product of another event. In this case,the event could well be the invention of cooking.
“The chin began to appear as a result of major changes six million years earlier. The arrival of cooking and softer food meant humans no longer needed big teeth and powerful jaws .and over the next two million years to 200,000 years both got smaller and the chin was bora ,” said Dr Pampush. “My guess is that it most likely happened around two million years ago when there was a jump in brain size. The changes which finally lead to the chin are directly related to cooking,and indirectly related to larger brains and bodies."
Dr Pampush's new theory goes against previous suggestions that the chin was an example of sexual selection,with attractive chins marking out men who are likely to make good mates(配偶) . The fact that both men and women have chins means the theory is unlikely.
Another theory put forward in the past said that the chin was a way to balance out the stress of chewing,but Dr Pampush also threw doubt on that idea.
1. The reason why we have chins .
A. is connected to humans’ action of chewing
B. has something to do with cooking
C. is random genetic change
D. is related to eating time
2. How did the researchers get their result?
A. By carrying out experiments. .
B. By studying scientific theories.
C. By examining the human brain.
D. By comparing recorded information.
3. Before developing chins,humans .
A. had bigger teeth
B. cooked softer food
C. had smaller jaws
D. had larger bodies
4. According to Dr Pampush,the chin most
probably appeared around .
A. 6 million years ago
B. 4 million years ago
C. 2 million years ago
D. 0.2 million years ago
5. What does the underlined part “the theory” refer to?
A. Men are likely to have more attractive chins.
B. The chin helps humans attract a mate.
C. Both men and women have chins.
D. Dr Pampush's theory.
8. Under our education (制度) ，you’ re supposed to be able to choose the type of schooling that your child receives.
3. We were just chatting what we did last weekend.
4. 湖边树木环绕。
The lake trees.
1. He was of medium height,but had very b shoulders.
2. My mother was (please) that I chose a college close to home.
7. It is still open to question is to head the group.
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