be quick/slow/first etc off the markinformalUNDERSTAND to be quick, slow, first etc to understand things or react to situations 反应快/反应慢/第一个作出反应等 You’ll have to be quick off the mark if you want to find a job around here. 如果你想在这儿找到工作，动作就得快。
be quick/slow/first etc off the mark• Salad crops, however, are quick off the mark.• This time, they were slow off the mark.
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