它可以表达愿望、假设、建议、命令、要求、条件、疑问等。

They can express willingness, supposition, suggestion, order, requirement, condition, question ect.

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这节课中，我们将学习使用条件从句表达愿望。我们将听到一个有关梦想的访问并学习一些新的词汇。

In this lesson, we will learn to express wishes using the second conditional. We will listen to an interview about dreams and learn some new vocabulary.

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梦作为人表达愿望和情感的方式和手段之一，自古以来，被作家们以各种方式借用，以表达自己的意愿。

One of the means by which human desires and emotions are expressed, dreams have, from ancient times on, been employed by writers in various ways to express their aspirations.

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And in fact in one with the girl describing her side, she several times emphasizes this need for protection, need to be free from being torn down from people around them.

事实上像一个女孩子表达的那样，她好几次强调了需要保护的愿望，需要逃离那些打倒她的东西,逃离身边的人们。

麻省理工公开课 - 媒体、教育、市场课程节选

It's a very easy, very direct, not at all impolite way to express your desires in any situation.

这是个非常简单而直接的句型，用这样的句型在各种情形下表达你的愿望也不会显得不礼貌。

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And the doctor told me it is good for me to express my creative urges.

医生也告诉我,表达出我自己强烈的愿望对我有好处。

麻省理工公开课 - 固态化学导论课程节选