【名词&注释】
化学性质(chemical properties)、相对原子质量(relative atomic mass)、可燃性(flammability)、核外电子(extranuclear electron)、不允许(not allow)、第三人称单数(the third person singular pronoun)、化合反应(combination reaction)
[单选题]氧气是我们身边常见的物质，以下有关氧气的叙述正确的是
A. 物质与氧气发生的反应都是氧化反应
B. 鱼、虾等能在水中生存，是由于氧气易溶于水
C. 氧气具有可燃性
D. 物质在氧气中燃烧的反应一定是化合反应(combination reaction)
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举一反三：
[单选题]29．
A. watch
B. watching
C. watchs
D. watches
[单选题]4． Lily is___________ taller than her sister．
A. a few
B. few
C. a little
D. little
[单选题]Once a man and his wife worked for a businessman． There was a big box in the business-man-s living room． The businessman pointed at the box and said，"There's only one thing you(11) do．Don't open the box． After saying this，he(12)the living room．The woman said to her husband，"There (13) be something expensive in the box． Let's (14) it，shall we? Her husband said no to her．
A. Her husband didn't stop her． She opened the box and looked (17) ．She found nothing in the box and tried hard to close it，(18) she failed．
B. ' He was Very an gry and asked the woman and her husband to leave his home．
C. "We haven-t taken anythiny (20)．"The businessman shouted at them，"The box is not important． I cannot believe you．That’s important!" '
E. needn’t
F. wouldn’t
G. mustn’t
H. shouldn't
[单选题]CIn most situations, light helps us see. But nowadays humans are using too much of it so that it is in fact a kind of pollution.
A. When it comes to looking at the night sky, too much light makes it difficult for us to watch some of life’s most wonderful sights: stars, planets and even galaxies(星系).
B. According to scientific research, about 2, 500 stars can be seen by the human eye without using any special equipment(设备). But because of light pollution, you can only see 200 to 300 stars from today’s countryside, and no more than ten stars from a city. In most big cities, people cannot see the sky filled with stars like they did in their childhood.
C. Light pollution affects more than just our view of sky. Research shows that lots of nighttime light can harm wildlife, too.
D. When birds fly to another place over cities, they sometimes get lost by the brightness and fly in circles(圈) until they drop from tiredness. Sea turtles(海龟) need dark beaches for laying eggs, but they can’t find their ideal places because of those bright lights.
E. Too much light at night may even affect human health, but scientists are not sure of that. They are still learning more.
F. In order to prevent things from going worse, governments and some organizations are working to reduce light pollution. Many cities and towns have taken action to reduce the use of lights at night. Lights are used only when and where they are truly needed. They also shine lights down at the ground instead of up into the sky and use lower brightness levels.
G. Hopefully, in the near future, humans can enjoy the clear and beautiful sky again and all the wildlife will live a peaceful and undisturbed life, too.
H. 27. Why does the writer think that too much light is a kind of pollution?
I. Because there are fewer and fewer stars.
J. Because human health has been affected.
K. Because too much light is a waste of energy.
L. Because some of the wildlife can be harmed.
[单选题]22． What kind of movies do many young people like?
A. Thrillers
B. Action movies
C. Cartoon movies
D. Beijing Opera
[单选题]与元素的化学性质关系最密切的是（ ）
A. 元素的相对原子质量
元素的核电核数
原子的核外电子数
原子的最外层电子数
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