男女同学之间正常交往，是学校生活的一项重要而不可缺少的内容，它有利于（  ）
①增进男女同学之间的相互了解，相互学习，完善个性      ②激发内在的积极性和创造性，提高学习和活动效率
③扩大交往范围，提高交往能力                                              ④男女生“早恋” 

20世纪的战争与和平

材料一：美国对德国的统一持积极支持的态度，但支持德国的统一是有条件的。强调德国统一必须在联邦德国继续同北约和欧共体保持联合的情况下实现，“不应以中立换取统一”。英国对德国的统一开始持消极的态度……法国对德国统一的心情是矛盾和疑虑的，在开始时也是持不积极支持的态度。

材料二：两德合并大大增加了新德国综合实力。在德国统一之前，原联邦德国和民主德国分别是西欧、东欧集团（前苏联除外）中经济实力最强的国家。……两德统一之初，新德国在经济上是任何一个欧洲国家所无法相比的，成为欧洲经济上的“超级大国”。两德统一，又为德国的继续发展和进一步崛起提供了机遇，扩大了德国在国际上的地位和影响，在德国的主动努力下，l991年12月11日，欧共体12个成员国政府首脑签署了关于建立欧洲政治联盟和经济货币联盟的《马斯特里赫特条约》。

——吴友法、邢来顺《德国：从统一到分裂再到统一》

    She is a cute, quiet girl. As a daughter, she has no secrets from her mother, who is very pleased with her. But these days she has become not so open as before. She has a diary that she keeps under lock and key. Her mother cannot help worrying about her: What will I do if she falls in love, which is too early of her age? After all she is reaching the "dangerous time". These thoughts have caused trouble in the mother's mind.

    One weekend the girl came to tell her mother that she was going to the cinema with her schoolmate and would return late. This was the first time her mother agreed, and she couldn't help worrying because her daughter had never been away at night before. The mother waited till nine. She decided to go out to meet her daughter. Just at that time, she heard the noise of a car parking. She went to the window and saw her daughter waving goodbye to a boy. Her heart missed a beat.

    When the girl came in, the mother was watching TV, just like nothing had happened. "Mum, I'm going to bed."

    "All right. Go to sleep early."

    The next morning when the mother went to the daughter's room to do some cleaning, she found her diary left on the bed. After a few minutes' thinking, she at last opened it to the page of the night before. It reads: Mum, it's love that made you ask, but it would show your understanding of me if you hadn't.

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