题干

下图中的①、②是氟元素、钙元素的信息,A、B、C、D是四种粒子的结构示意图。

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上一题 下一题 0.0难度 选择题 更新时间:2018-04-16 11:16:40

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同类题3

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I'm David.When I was 13,my parents decided that I should go to England to improve my English.I had never been to other countries before,so I felt a little worried.My parents prepared everything for my journey.My plane was due(预期)to leave at 9:30 a.m.and arrive in two hours.I phoned the English family who I would stay with and they told me they would wait for me at the airport(机场).

Unluckily my plane to London was delayed (延误).I tried to phone the English family again but I couldn't speak to them because they had already left home for the airport.

When I arrived in London.it was already 1:30p.m.I went to get my luggage(行李)but I couldn't find it.I became very worried.Luckily, the airport staff(工作人员)was very helpful and efficient.I didn't wait long-they found it 10 minutes later.

My English family were still waiting for me! I was so happy! Then my new life in London began.My English family were quite kind.I learned a lot of English because I spent most of the day talking in English.I played computer games with the little boy in my English family.I also taught him how to play chess.Sometimes I told him stories I learned from my family.

I missed my family during my stay in London.but I also feIt sad when my stay there came to an end.My English family held a party for me.I enjoyed it very much.I’ll never forget that summer in London! It is one of the most wonderful experiences I've ever had.

同类题4

阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项。

    On a cold winter evening, I was walking home alone, when suddenly came screams (呼喊声) from behind some tress.1 I slowed down to listen, and 2 that what I was hearing were the sounds of a fight. A woman was being attack (袭击) not far from where I 3.

     “Should I go to help her?” I thought. I was worried about my own 4 , and I regretted having suddenly decided to take a new way home that night. “What if I am 5 too? Shouldn't I just6 to the nearest phone and call the police?” But already the girl's 7 were growing weaker. I knew it was time for me to act fast because I could not 8 the life of this unknown woman, 9 it meant risking my own life.

    I am not a 10 man. I didn't know where I found the 11  and physical strength (体力), but once I had finally 12 to help the girl, I changed suddenly. I ran behind the bushes and 13 the attacker off the woman. Struggling, we fell to the ground, where we fought for a few minutes 14 the man jumped up and ran away.

    15 heavily, I came up to the girl, who was crying. In the 16 I could not see her clearly, but I could certainly 17 her shock. Not wanting to frighten her any further, I spoke to her from a distance.

     “It's OK,” I said 18“The man ran away. You're safe now.” There was a long stop and then I heard the words, said in both wonder and 19 “Dad, is that you?” And then, from behind the tree, stepped my youngest 20 Katherine.