How did that other frog learn to turn itself into a bouncy ball and roll down hills away from danger?

某些特殊的蛙类怎么学会把身体团成一个有弹性的球滚下山崖以逃避危险？

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Then, with the handle either still attached or removed, the ball becomes a plaything that users can roll, kick and have fun with to agitate the clothing within.

滚至水源点后，可以取下手柄，也可以不取下手柄。 这种洗衣机变成可以滚，可以踢的球，同时也可以嬉戏着搅动衣物。

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Put the ball carefully on the table, so that is won't roll off.

球放到桌上时要小心，别让它滚下来。

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An example closer to everyday experience is that of a ball placed at the crest of a hill, which might roll into any of several valleys depending on slight differences in its initial position.

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