拓扑是一门数学，它研究的对象是物体在平滑变形(例如伸长、挤压、弯曲、但不得切断或连接起来)之下仍会保持不变的性质。

Topology is the mathematical study of properties that are unchanged when an object is smoothly deformed, by actions such as stretching, squashing and bending but not by cutting or joining.

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拓扑是一门数学，它研究的对象是物体在平滑变形(例如伸长、挤压、弯曲、但不得切断或连接起来)之下仍会保持不变的性质。

Topology is the mathematical study of properties that are unchanged when an object is smoothly deformed, by actions such as stretching, squashing and bending but not by cutting or joining.

youdao