1、 Upon reaching the coast,the lemmings do not stop but swim by the thousands into the surf.
一旦到达海岸，旅鼠不会停下来，而是成千上万地游进海浪中。
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2、 When their food supply is sufficiently large, the lemmings live a normal, undisturbed life.
当它们的食物供给量足够大时，旅鼠过着正常的、不受干扰的生活。
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