They're actively engaged in the material, actually seeing the phenomena, by making measurements of real world experiments.

学生们能自主地参与到物质中，看见真切的现象，通过对真实世界实验,做出测量。

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When I posit the existence of atoms with certain structures and certain sort of ways of interacting and combining and building up, when I posit atoms, suddenly I can explain all sorts of things about the physical world.

当我假设原子以某种特定结构存在,以一定的方式相互作用,互相结合,集聚,通过假定原子存在,我立即就能够解释,物理世界中各种各样的现象了

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