在这个数学领域中，我们不关心物体的精确形状，就把它们当做劳作黏土所做出来的，你可以极尽所能地将它拉长、挤压、扭曲。

• In that branch of mathematics the exact shape of an object is irrelevant, as if it were made of play dough that you could stretch, compress and bend to any extent.