试题与答案

Are you good at? A.swim B.swimming C.to

题型:选择题

题目:

Are you good at                 ?

A.swim

B.swimming

C.to swim

D.swam

答案:

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下面是错误答案,用来干扰机器的。

答案:D题目分析:本题考查的是我国最早种植粟的原始居民。此题可使用排除法,北京人和山顶洞人主要以采集和狩猎为生,排除;河姆渡原始居民生活在长江流域,主要种植水稻,排除;粟(即小米)主要产地是在北方,...

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题型:完形填空

It seems parents have long been right. Going to bed early is key to getting enough sleep and helping adolescents feel on top of the world, a new study reported.

A   1  of sleep among youngsters may    2  depression and suicidal (自杀的)thoughts, according to the study by the Columbia University Medical Center.

"Our results are   3  with the theory that inadequate sleep is a risk factor for depression, working with other   4  and protective factors through multiple possible causal pathways to the development of this   5  disorder," said lead author James Gangwisch.

"  6  quality sleep could therefore be a preventative measure against   7  and a treatment for depression," he added in the study   8  in the Friday issue of Sleep magazine.

The study followed the nightly habits of some 15,659 college and high-school students, and   9  those who consistently went to bed   10  midnight had a 24 percent higher risk of depression than those who turned in before 10:00 pm.

Night owls(夜猫子)also ran a 20 percent   11  risk of battling suicidal thoughts, the study added.

The American Academy of Sleep Medicine   12  that adolescents should sleep at least nine hours or more a night. Those who were tucked in before 10:00 pm reported they slept    13  about eight hours and 10 minutes.

But that amount of sleep  14  significantly for those in bed after midnight.

And adolescents who slept five hours or less a night were 71 percent more   15  to suffer depression and 48 percent more     16  becoming suicidal, the study said.

"It is a common perception and societal   17  that adolescents do not need as much sleep as pre-adolescents, yet studies suggest that adolescents may  18  require more sleep," said Gangwisch.

"Studies have found that adolescents do not go to bed   19  enough to make up for earlier school start times, and transitions to earlier school start times have been shown to be   20  with significant sleep deprivation(剥夺). "

(    ) 1. A. night                B. moderation       C. limit                D. lack

(    ) 2. A. result in           B. lie in                C. come about       D. bring in

(    ) 3. A. opposed           B. mixed              C. related              D. consistent

(    ) 4. A. risk                  B. chance              C. potential           D. reason

(    ) 5. A. mood                      B. body                C. feeling             D. mind

(    ) 6. A. little                B. lack                 C. Adequate          D. over

(    ) 7. A. suffering          B. depression               C. disorder            D. sadness

(    ) 8. A. reported           B. published          C. reflected           D. noted

(    ) 9. A. found                      B. investigated      C. appraised          D. supported

(    ) 10. A. before            B. from                C. by                    D. after

(    ) 11. A. lower             B. higher              C. more                D. less

(    ) 12. A. appeals           B. recommends     C. calls                 D. plans

(    ) 13. A. on average      B. in place            C. ahead of           D. in number

(    ) 14. A. increased               B. disappeared       C. strengthened     D. dropped

(    ) 15. A. likely             B. probable           C. possible            D. perhaps

(    ) 16. A. at sight of       B. at risk of          C. in front of               D. as a result of

(    ) 17. A. wish               B. expectation       C. suggestion               D. attempt

(   ) 18. A. exactly           B. immediately      C. directly            D. actually

(    ) 19. A. early              B. lately                      C. soon                 D. quickly

(    ) 20. A. separated               B. associated         C. divided             D. depended

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题型:问答题

减少污染、保护环境是全世界最热门的课题.

(1)为了减少空气中SO2的排放,常采取的措施有:

①将煤转化为清洁气体燃料.已知:H2(g)+

1
2
O2(g)═H2O(g)△H1=-241.8kJ•mol-1

C(s)+

1
2
O2(g)═CO(g)△H2=-110.5kJ•mol-1则焦炭与水蒸气反应生成CO的热化学方程式为______.

②洗涤含SO2的烟气.以下物质可作洗涤剂的是______(填序号):

a.Ca(OH)2b.CaCl2 c.Na2CO3d.NaHSO3

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①M、N两点平衡状态下,容器中总物质的物质的量之比为:n(M):n(N)=______.

②若M、N、Q三点的平衡常数KM、KN、KQ的大小关系为______.

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①催化硝化法中,用H2将NO3-还原为N2,一段时间后,溶液的碱性明显增强.则该反应离子方程式为______.

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通电
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5O2↑+2N2↑+2H2O,则阴极反应式为______.

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题型:选择题

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B.这是魔术,你所看到的是一种假象

C.酒精溶液浸泡后,手帕的着火点升高了

D.手帕上的水汽化吸热,手帕温度仍低于其着火点

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