To go head-to-head意思是两人之间头对头地竞争。
　　例句：
　　They're both amazing swimmers - I can't wait to see them go head-to-head.
　　There can only be one winner. We'll have to go head-to-head to decide who it is.
　　注意：
　　还有一个意思类似的短语是neck-and-neck，它的意思是在竞争或竞赛中不相上下。
　　例句：
　　At this stage, either of them could win. It's neck-and-neck!
　　英语中还有很多类似结构的短语，比如eye-to-eye, face-to-face, cheek-to-cheek, shoulder-to-shoulder或back-to-back不过他们的意思各不相同！
　　常识补充：
　　The head can send a wide variety of body language signals. A lowered head can be a defensive posture that occurs as a result of a perceived threat. Touching the face is often seen as a sign of anxiety and people have regular places they touch when they are worried. Our heads are quite heavy, so when we are tired we may use our hand and arm to prop it up. Sometimes when we are thinking, we may also prop up the head.
　　我们的头部可以发送各种各样的身体语言信号。低着头可以代表对“威胁”的自我保护姿势。有些人在碰到担心忧虑的事情的时候，会触摸头的某一部分，这就显示了他们焦虑情绪的迹象。我们的头部是相当沉重的，所以当我们累了的时候，我们会习惯用我们的手和手臂来支撑它。当我们在思考问题的时候，我们可能也会托着下巴来支撑头部。

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