Salmon manage to swim upstream to lay their eggs.

三文鱼设法游到上游产卵。

《柯林斯英汉双解大词典》

The barriers are lethal to fish trying to swim upstream.

这些障碍物对于逆流而上的鱼来说是致命的。

《柯林斯英汉双解大词典》

It means to swim upstream because the stream is flowing into the foul pit of destruction.

它意味着要逆流游泳，因为河水正在流入到毁灭的污水坑中。

youdao

That means that the euro will have to swim upstream for another three to four years.

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The few brave statesmen seeking fiscal restraint swim upstream against the media, education establishment and entertainment industries.

FORBES: Newt Gingrich Highlights Republican Futility On Spending

And as long as public opinion flows in that direction, politicians are unlikely to try to swim upstream.

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