题目内容

钓鱼岛（The Diaoyu Islands）自古就是我国固有领土，又称钓鱼台、钓鱼台群岛、钓鱼台列岛，位置在距温州市约356km、福州市约385km、基隆市约190km．若我国某海监船为维护我国对钓鱼岛主权，从温州出发去钓鱼岛巡航，到达钓鱼岛时航行了480km．则下列说法中不正确的是（）
A．该海监船位移是480 km，路程356km
B．该海监船位移是356 km，路程480 km
C．该海监船在海上航行时，确定其位置时可以将该海监船看成质点
D．若知道此次航行时间可求出此次航行的近似平均速度

【答案】分析：位移是矢量，有大小，有方向，可以用由初始位置指向末位置的有向线段表示；路程表示运动轨迹的长度，在单向直线运动中，位移的大小等于路程．
能否看作质点物体本身无关，要看所研究问题的性质，看物体的形状和大小在所研究的问题中是否可以忽略．平均速度等于总位移除以总时间．
解答：解：A、位移是矢初始位置指向末位置的有向线段的长度，所以位移为356 km，路程表示运动轨迹的长度，所以路程为480 km，故A错误，B正确；
C、该海监船在海上航行时，其大小和形状对其位置没有影响，所以可以看成质点，故C正确；
D、平均速度等于总位移除以总时间，知道位移和时间即可求解平均速度，故D正确．
本题选错误的
故选A
点评：解决本题的关键理解路程和位移的区别及联系：位移是矢量，有大小，也有方向，可以用由初始位置指向末位置的有向线段表示；路程表示运动轨迹的长度，只有大小，没有方向．在单向直线运动中，位移的大小等于路程．

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－Have you finished reading ________ interesting story?

－Yes．It is worth reading ________ second time．

[　　]

A．the; a

B．an; the

C．the; the

D．an; a

_______,Mother will wait for him to have dinner together．

[　　]

A．However late is he

B．However late he is

C．However is he late

D．However he is late

Dear Chicken Soup for the Teenage Soul,
Most people don’t really know what pressures a typical teenager has to go through. Sure, our parents and grandparents were once teens, but things are so different now. It has never been to tougher (严格)to a teenager.
It had never been more important to be in the “right group” or to have the “right brand” of shoes. And those are the easy things to deal with. We also face problems with family, friends, relationships and school pressures.
When it gets to be too much, I turn to my friends. One friend I could not live without is Chicken Soup for the Teenage Soul. Your books have been so inspiring to me and have helped me to deal with and understand the problems I go through.
For example, I went through a confusing time with my friends when we got to junior high. I had known these friends since kindergarten, and when we began junior high it seemed like some of them began to change. We started hanging out with different groups, and we slowly grew so far apart that it seemed as if we had never been friends. I felt confused and hurt.
Sometime during this period I read the story Friends Forever in Chicken Soup for the Teenage Soul Ⅱ.I felt so much better after reading it. It was like a weight had been lifted from me when I realized that many friendships went through changes and that we weren’t the only friends to experience them.
People change, but that doesn’t mean we have to lose the friendships we once shared. My friends and I still spend time together when we can and care about each other a lot. That things are different doesn’t mean I have to forget about all the good times we had. I will always keep the memories in a safe place in my heart.
Sincerely,
Peter
【小题1】According to the author, parents and grandparents

A．didn’t have to overcome difficulties when in their teens.

B．don’t fully understand the pressures of being a teenager now

C．can easily deal with things such as choosing friends and shoes.

D．don’t need to give help to teenagers with pressures and problems

【小题2】Why did the author feel confused and hurt when he got to junior high？

A．Because he was afraid that he had lost his friends.

B．Because he and his friends weren’t in the same school.

C．Because he was too busy to be with his friends.

D．Because his friends refused to hang out with him.

【小题3】What does the underlined word “them” in Para．5 refer to？

【小题4】In the letter the author mainly tells us that

A．people change but friendships always last.

B．changes sometimes cause hurt and confusion

C．people will go through many changes in life

D．friendships should be kept with skills

Nuclear energy has always been controversial. But since the tsunami and nuclear disaster in Fukushima (Japan) last year the issue is back in the headlines. And the world is divided— some countries are planning more nuclear plants, while others have promised to shut theirs down.
After Fukushima, Germany decided to switch off all its nuclear plants by 2022. Switzerland and Italy are also phasing out nuclear power. But France and the United States remain staunch supporters of atomic energy. In fact, almost 80% of France’s electricity comes from nuclear power, the highest percentage in the world. And in the US, the Obama administration said it “continues to support the expansion of nuclear power, despite the crisis in Japan.”
Nuclear supporters claim nuclear power can help the environment. Unlike fossil fuels, nuclear power doesn’t create greenhouse gases. So, pro-nuclear countries argue that nuclear power allows them to generate energy without contributing to climate change. Britain’s chief scientific adviser (John Beddington) supports this view. He recently said that the world doesn’t have the luxury of ignoring nuclear energy.
Nuclear power is also relatively cheap. Renewable energy sources such as solar, hydro and wind power may be clean, but they’re expensive; and right now, they require a lot of investment. This higher cost of using “green energy” is usually passed onto the consumer. So, while many people may prefer their energy to come from a renewable source, not so many are prepared to pay higher energy bills. This is of particular concern while the world economy is in such bad shape.
The main argument against nuclear energy is that it isn’t safe. For a start, nuclear waste is very difficult to dispose of, and remains toxic to humans for thousands of years. And even before Fukushima, there were several high-profile nuclear disasters. The most famous is probably the 1986 Chernobyl disaster, in the Ukraine. The radiation from the meltdown spread all over Europe, affecting thousands.
The nuclear energy issue is very complex. And it doesn’t look like it’ll be resolved anytime soon. As a Japanese commentator recently said, “it’s been a bad year for the ‘nuclear village’, but I don’t think they’re down and out yet.” The battle continues.

1.
Which of the following may NOT be the advantage of nuclear energy over other energy sources?
1. A.
  Nuclear energy doesn’t produce any greenhouse gases.
2. B.
  Nuclear energy can help prevent the climate damage.
3. C.
  Nuclear energy is more environmental-friendly than other green energy sources.
4. D.
  Nuclear energy can save the consumers some money, compared to other renewable energies.
2.
What does the underlined word “this” refer to in paragraph 4?
1. A.
  The fact that many people prefer to use the green energy sources while unwilling to pay higher bill.
2. B.
  The cost of using renewable sources
3. C.
  The fact that the nuclear power is cheaper.
4. D.
  The investment of renewable energy sources
3.
We can learn from the last paragraph that _______.
1. A.
  the Japanese commentator is positive about the future of nuclear energy
2. B.
  the nuclear energy issue will be soon settled
3. C.
  a battle will break out in the future
4. D.
  Japan is considering to build a nuclear village in the future
4.
What is the author’s purpose of writing the passage?
1. A.
  To highlight the danger of using nuclear energy.
2. B.
  To introduce some serious nuclear disasters.
3. C.
  To show the argument between nuclear supporters and protesters.
4. D.
  To give some advice on how to use nuclear energy safely.

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---- I think ________.

A. yes B. it C. that D. so

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We can learn from the last paragraph that _______.

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