They can do it on rare occasions, or they can do it whenever they feel like it, or they can do it regularly; it's often done quarterly.

他们可以偶尔为之,也可以在任何时间发放,或者定期发放,一般是一季一发

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And things got out of hand.

然后事情一发不可收拾了。

在工作室发生的事 - SpeakingMax英语口语达人