Tracking individual fish in a shoal is hard. Fortunately, advances in pattern-recognition software mean it is no longer impossible.

追踪鱼群中的个体十分的困难，幸运的是，外形识别软件的进步意味着它不再成为不可能。

youdao

If there's one hard rule of childhood, it's that kids don't like fish.

要说童年有什么不变的规律，那就是孩子们都不喜欢吃鱼。

youdao

Tracking individual fish in a shoal is hard.

跟踪记录鱼群中的个体很困难。

youdao

It is hard to imagine why anyone would want to shoot fish in a barrel.

VOA: special.2009.06.07

And he had seen days of no food and empty stomachs, days when the fish did not come, and the animals were hard to find.

VOA: special.2010.02.27

Still, the primal urge I felt to fish was hard to completely tamp down.

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Breakfast is always the same: some cold smoked fish, hard-boiled eggs, pungent natto (fermented tofu) and other leftovers from the night before.

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But the real thing to be excited about here is that Amarin may gather hard proof that giving fish oil to people with high triglycerides lowers their risk of heart attacks.

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