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.
一门科学或一部著作有众多的范畴，并不是任意一种连接顺序都能使之成为逻辑严密的系统。
A branch of science or a book includes in it a host of categories. Not any arrangement of these categories can make it a strict logical system.
从母亲的真实故事（或经历）中，我也感受到，掌握一门或几门外语的重要，它是了解世界的窗口，是连接友谊的纽带。
Mother has told some true stories about her past, from it I think, it's necessary to master one or several foreign languages. Because it's the window to know the world, and ties of friendship.
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