第2针本应只在第1针见效后才能注射。

The second injection should only have been given once the first drug had taken effect.

《柯林斯英汉双解大词典》

他们会检测你，以确定你已获得了足够的保护，有些人在测试完后需要再打一针。

They test you to make sure that you have adequate protection, and some people need an additional shot after that.

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打了一针激素后，不管每种气味有多么地刺激食欲，志愿者们都更深深地吸气，甚至只是吸普通的空气。

And regardless of how appetizing each aroma was, the volunteers took deeper whiffs-even of plain air-after getting a shot of ghrelin.

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Then they test you to make sure that you have adequate protection, and some people need an additional shot after that.

然后医生会检测以确定你已获得了保护,有些人在测试完后需要再打一针

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