knee jerk

基本解释

Initially the knee jerk is to sell JPY, but the reality is that JPY strengthens dramatically.
最初大家的反应都是卖掉日元，但事实上，日元会非常戏剧化的走强。
It's impossible to say hello without smiling. One leads to the other just as a tap causes a knee jerk.
说“你好”的时候，是不可能不面带微笑的，而且能一个传给另一个，正如敲击膝盖引起的条件反射。
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The knee jerk is a typical respondent .
膝反射是一种典型反射。
www.translation-dictionary.net

But she thoughtfully pleas for reasoned contemplation and discussion rather than knee jerk reactions.
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Or was it just the threat of a knee jerk reaction against an obviously fragile financial system?
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Personally, I would really like to see more umpire consultations after a close call rather than the knee jerk reaction for instant replay.
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