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》

Now, instead of swimming upstream, we relax, sleep, watch movies, or listen to music.

现在，我们不再逆流而上，而是放松、睡觉、看电影或听音乐。

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In the summer, bull trout forge 50 miles upstream from Lake Koocanusa to spawn in the Wigwam River drainage in British Columbia.

夏天，鳟鱼从 Koocanusa 湖逆流而上50英里，到不列颠哥伦比亚威格沃姆河的排水系统产卵。

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