问题 选择题

镁粉在焰火、闪光粉、鞭炮中是不可少的原料.工业上制造镁粉是将镁蒸气在某种气体中冷却,有下列气体:①空气、②氧气、③氩气、④氢气、其中可作为冷却气体的是(  )

A.①②

B.②③

C.③④

D.③

答案

首先我们要知道镁粉会和哪些物质反应.2Mg+O2=2MgO;3Mg+N2=Mg3N2;2Mg+CO2=2MgO+C.氢气在加热时容易发生爆炸,所以可以用氩气作冷却气体.

故选D.

阅读理解

The earth is changing. Tomorrow it will be different. All the living things on the earth are changing. Even people are changing, and tomorrow you will be different.

There are many kinds of change, and many different things than cause change. People need to realize the changes, to learn to see them, and to learn what causes change.

Human beings must solve many problems so that they can continue to live successfully. War is one of these problems. Disease and natural disaster are problems. Having enough food and energy for the growing number of people in the world is a problem. Most problems can be solved, but some are impossible to solve. The way in which people solve problems affects how long and how well they can live.

As people solve their problems, they change things, and changes often cause new problems for people and for other living things on the earth. Sometimes the new problems seem even worse than the old ones. Human beings will probably never stop having problems to solve. Can you use your imagination to describe a world that has no problems at all ?

小题1:The reason why everything is changing is that______.

A.people want them to be changing

B.there’re many different things that cause them to change

C.the living things are changing

D.the world is too small小题2:People need to solve problems because______.

A.there will be more and more new problems if they don’t solve the old ones.

B.the problems are difficult to solve

C.they have to go on living

D.there are so many things that are changing小题3:New problems appear ______.

A.because old problems aren’t solved.

B.because people don’t solve them

C.because some people are foolish

D.when people are solving old ones小题4:Which of the following if wrong according to the passage ?

A.Disaster and war are two of the problems people have to solve.

B.People need to solve all the problems at the same time.

C.The way people solve problems has much to do with their life.

D.People can’t solve all the problem at one time.小题5:The underlined word “disaster” in the passage probably means “______” in Chinese.

A.灾难

B.资源

C.条件

D.环境

阅读理解

Lynn is the publisher of Indiana Living Green magazine, a local Indiana-based publication focusing on all issues related to leading a sustainable lifestyle. Her knowledge, passion and unwavering dedication to this cause are both inspiring and admirable and are the reasons I nominate her for the Heart of Green Local Hero.

Lynn's interest in sustainable living has expanded over the years from simple recycling and wildlife gardening to encouraging others to appreciate nature and do what each can to protect the environment. The creation of Indiana Living Green comes from her belief that most individuals have an inner desire to do what is best for our environment and that each individual act truly does make a difference.

Lynn has been instrumental in bringing her green consciousness to Indiana by way of Indiana Living Green magazine over the past two years. Indiana Living Green is the only local publication solely focused on green living and sustainability. In addition, Lynn’s pioneering efforts also provide public educational forums via "Green Scenes" — a series of three hour events, each focusing on specific topics teaching Hoosiers how to lead greener lifestyles. She is a sought-after speaker, delivering topics such as "Greening Your Outdoor Space," "Updating Your Home to Green" and "Greening Your Lifestyle" to various businesses and organizations throughout Central Indiana. In addition, Lynn has appeared regularly on Indianapolis Fox 59 morning show’s "Living Green" segment, discussing various topics of interest ranging from grilling green and green baby buys to composting and recycling.

In addition to her role as publisher of Indiana Living Green magazine, Lynn is also a Habitat Steward Host for National Wildlife Federation, editor of Hoosier Organic Gardener, the newsletter of the Indiana Organic Gardeners Association, and a member of Garden Writers Association.

Lynn Jenkins deserves to be publicly recognized for all that she is and all that she has done and continues to do to educate and empower each of us to improve our individual lives, communities and our Earth.

小题1:Which of the following is NOT true of Lynn Jenkins?

A.She is the publisher of the magazine Indiana Living Green.

B.She is a member of Garden Writers Association.

C.She won the award the Heart of Green Local Hero.

D.She encourages people to love and protect nature.小题2: Indiana Living Green was probably _________.

A.a book on modern life style

B.a magazine on fashion

C.a journal on travel

D.a magazine on green living小题3: What can we learn about “Green Scenes”?

A.It is a scene set in a three-hour film.

B.It is a series of events focusing on green life.

C.It is a film set in Central Indiana.

D.It is a forum focusing on green lifestyle.小题4: The underlined word in the third paragraph probably means ________.

A.simply

B.mainly

C.earnestly

D.seriously小题5: What is the purpose of the writing?

A.To call on readers to protect the environment and live green.

B.To nominate Lynn Jenkins for the Heart of Green Local Hero.

C.To introduce the readers to the Heart of Green Local Hero.

D.To advertise for Indiana Living Green and its publisher.