[单项选择]In the world in which we live today, a man may be one thing but appear to be another. This was impossible in Indian society. An Indian’s name told the world what he was — a coward, a liar, a thief, or a brave.
When I was young, every Indian had at least three names during his lifetime. His first name was given to him at birth.
Each Indian was supposed to keep his birth name until he was old enough to earn money for himself. But his friends would always give him a name of their own. No matter what his parents called him, his childhood friends would use the name they had chosen.
The Indian earned his real name when he was old enough for his first fight against the enemy. His life name depended on how he acted during this first battle. When he returned he would be given his tribal name by the chief. If he had done well, he would be given a good name. But if he had done poorly, he night be given a bad name.
A man was given ninny chances to improve his name, however. If

[单项选择]In the world in which we live today, a man may be one thing but appear to be another. This was impossible in Indian society. An Indian’s name told the world what he was — a coward, a liar, a thief, or a brave.
When I was young, every Indian had at least three names during his lifetime. His first name was given to him at birth.
Each Indian was supposed to keep his birth name until he was old enough to earn money for himself. But his friends would always give him a name of their own. No matter what his parents called him, his childhood friends would use the name they had chosen.
The Indian earned his real name when he was old enough for his first fight against the enemy. His life name depended on how he acted during this first battle. When he returned he would be given his tribal name by the chief. If he had done well, he would be given a good name. But if he had done poorly, he night be given a bad name.
A man was given ninny chances to improve his name, however. If

[单项选择]Many people in the world live in big cities, which are often dirty and difficult places to live in. So, some cities will get bigger. They will also get higher, and lower, because people will begin to live under the ground as well as in tall buildings. Scientists also say that men can begin to live in cities under the sea, when there is not enough space on the land. Of course, these new cities will be very expensive, and difficult to build, but they are not impossible. Already, some countries are building places to live under the ground so their people can go there if there is a new war. There are underground cities in Switzerland and China, built by the government to help some of the people live after a great war.
But will the people change if they live under the ground for a long time For example, some fish go blind if they live in the dark for a long time. People will not go blind, because there will be light underground, but they may change in some way. Scientists say that peop
A. it’s neither hot nor cold there
B. they’ll be afraid of the war
C. there ’11 be less space on the ground
D. they’ll make their life comfortable

[单项选择]If you go down to the woods today, you may meet high-tech trees-genetically modified to speed their growth or improve the quality of their wood. Genetically-engineered food crops have become increasingly common, albeit controversial, over the past ten years. But genetic engineering of trees has lagged behind.
Part of the reason is technical. Understanding, and then altering, the genes of a big pine tree are more complex than creating a better tomato. While tomatoes sprout happily, and rapidly, in the laboratory, growing a whole tree from a single, genetically altered cell in a test tube is a tricky process that takes years, not months. Moreover, little is known about tree genes. Some trees, such as pine trees, have a lot of DNA-roughly ten times as much as human. And, where- as the Human Genome Project is more than halfway through its task of isolating and sequencing the estimated 100,000 genes in human cells, similar efforts to analyze tree genes are still just saplings (幼苗)
A. began much later
B. has developed more slowly
C. is less useful
D. is less controversial