knee jerk

基本解釋

Initially the knee jerk is to sell JPY, but the reality is that JPY strengthens dramatically.
最初大家的反應都是賣掉日元，但事實上，日元會非常戲劇化的走強。
It's impossible to say hello without smiling. One leads to the other just as a tap causes a knee jerk.
說“你好”的時候，是不可能不面帶微笑的，而且能一個傳給另一個，正如敲擊膝蓋引起的條件反射。
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The knee jerk is a typical respondent .
膝反射是一種典型反射。
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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