溴乙烷在不同溶剂中与NaOH发生不同类型的反应，生成不同的反应产物． 反应类型

在中华人民共和国境内，是指生产、委托加工和进口属于应当缴纳消费税的消费品的（）在境内。

A.起运地

B.所在地

C.实质加工地

D.到达地

重型再障Ⅰ型的临床特点包括（）

A.发病急，贫血呈进行性加剧

B.常出现严重感染及内脏出血

C.外周血血红蛋白下降速度快，网织红细胞＜1%或其绝对值＜15×10⁹/L

D.白细胞明显减少，中性粒细胞＜0.5×10⁹/L

E.血小板＜20×10⁹/L

My secret of staying young is quite simple：devote your attention to the part of you that’s young and growing—your brain. Keep your mind awake and you will stay young all over. These are exciting times. Take an interest in the world around you，and make a point of learning one new thing every day.

No matter how old you are ，it’s not too late to make your life more interesting. I know a housewife without knowledge in the past who made herself into an excellent industrial designer. I know an old electrical engineer who has become a highly paid artist.

Get over the idea the you are too old to go back to school. I know a man who entered a medical college at 70. He got his degree with honors and became a famous doctor. Another man went to a law school at 71 and now is an active lawyer.

No matter how old people are，staying young is easy for those who live in the future. You can do it if you are active enough to try. Keep your mind active and awake：that’s the only youth elixir.

54. Which of the following best express the main idea of this passage？

Staying young is the only youth elixir.

Learning at least one new thing every day.

Never too late to go back to school.

The secret of staying young.

55.  If you wish to stay young，above all ，you should        .

A. keep your mind awake and active      B. make your life more interesting

C. keep your mind from being harmed     D. keep in tough with other people

56. The implied meaning of the passage is that        .

A. anyone can learn to do something no matter how old they may be.

B. the electrical engineer learned to be an artist to become famous.

C. the man who entered the medical collage at 70 came out at the top of the list.

D. every one can be successful if you try to learn no matter how old he may be

57. The word “elixir”in the last sentence probably means something that can keep people        .

A. healthy             B. wealthy            C. young               D. happy

顶芽自剪现象发生在（）分枝和（）分枝习性的树种中，致使枝条交替曲折延伸。

1.Passage 1
It is a pleasure to be here today to commemorate the first Earth Day with you by looking through this "Window on the American Environment". While I have not yet viewed the television series, from the accompanying book I can see that it is a very ambitious effort. The producers have interviewed a large number of environmental leaders in the United States, from early founders back in the 1970s through those involved in the contemporary movement. //
I am sure you will hear many different opinions, because the diversity of the American environmental movement is part of its strength. The ability of individuals and non-governmental organizations to express their opinions and make their voices heard in the press and in the electoral process is the root of the movement and why it flourishes today. I vividly remember going outdoors with my elementary school class on Earth Day 1970 to examine our environment by looking at what grew in the pond behind our school. The motto of that first Earth Day was "think globally, act locally", and our young teacher wanted us to better understand what was right around us. //
Nowadays teachers have access to all sorts of wonderful educational materials to help students study the environment and learn about concepts like biodiversity, climate change and protection of the ozone layer that were still foreign to us in 1970. But we knew then about toxic chemicals, deforestation, water pollution—the subject of our pond study—and land use issues, and we were learning to understand how much of an impact these could make on our futures. //
Earth Day 1970 was a novel idea proposed by individuals—not a government—that grew on its own, so that in that very first year, over 20 million Americans participated. We said, "think globally", but Americans were not yet thinking as much beyond their borders as we do today. Equally it would have been unimaginable in 1970 that China would air a 22-part television series on the United States. It would be another two years before the images of President Nixon’s famous trip to China would be broadcast on our television screens in the United States and we started to have the opportunity to learn about each other. //
Today the United States and China have a great deal to celebrate together for Earth Day. We are working together in areas from water conservation to the protection of endangered species to the development of new, cleaner sources of energy. We have an active program to work with Beijing to support its goal of a Green Olympics in 2008. Together we are researching climate change and exploring the possibilities for using hydrogen and fusion as energy sources. The United States government, through agencies like the Environmental Protection Agency, the Department of Energy, the Fish and Wildlife Service, the National Parks Service and dozens more has an active program of cooperation with its Chinese counterparts. //