swim or sink 浮不起来，就等着沉下去，用以期许对方“努力求生、自求多福、不进则退、成败全凭自己”。

【例句】
My employer gave me no help when I started my new job - I was just left to sink or swim.
开始新工作时，我的老板没有为我提供任何帮助——全凭我自己打拼。

After I’ve studied and learned all I can, I have to take the test and sink or swim.
在尽努力学习之后，我必须参加考试，要么成功，要么失败。