随着它向外生长，空间扩大，增大为以前的两倍，成了马鞋的形状。

As it grows outward, it runs out of room and is forced to double back into a horseshoe shape.

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用于马鞋、运动鞋、工作鞋、休？鞋、海绵鞋、婴儿鞋、高级皮革鞋类缝制。

For boots shoes, work shoes, leisure shoes, foam rubber sole pads, babies shoes and high quality leather shoes.

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狗、猫、马、鞋—哪一个不属同类？

Dog, cat, horse, shoe—which is the odd one out?

《牛津词典》