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问题 选择题

X、Y是第二或第三周期的元素，它们可以形成离子化合物XmYn，且离子均具有稀有气体的电子层结构，若X的原子序数为a，则Y的原子序数不可能是

A．a＋8－m－n

B．a＋16－m－n

C．a－8＋m＋n

D．a+m－n

答案

答案：D

填空题

短文填空。

     The best way of learning a language is by     1      (use) it.  The best way of learning English is talking

in English as     2     (many) as possible. Sometimes you will get your words mixed up (混淆) and people will not understand you. Sometimes people will speak too quickly and you can't understand them. But if

you keep your sense of humor (幽默感),  you can always have a good laugh at the mistakes. Don't be

unhappy if people seem     3     (be) laughing at your mistakes.  It is much    4     (good) for people to be

laughing at your mistakes than to be angry because they don't understand what you are saying. The most

important rule for learning English is: " Don' t be afraid of making    5      (mistake), everyone makes

mistakes."
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选择题

二战后，两个德国和两个朝鲜的出现（     ）

A．与雅尔塔会议直接相关

B．是美苏全面冷战的产物

C．是北约和华约对峙的结果

D．是反法西斯斗争的结果
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