He further predicted that every elementary particle with a spin has its counterpart with the same mass but opposite electric charge, or that a particle has an antiparticle.

他进一步预言每一种自旋为的基本粒子都有质量相同但电荷相异的对应粒子，或者说，就是每个这样的粒子都有一个反粒子。

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An elementary particle in the lepton family (not a meson), having a mass209 times that of the electron, a negative electric charge, and a mean lifetime of2.2? 0-6 second.

介子轻子族中的一种基本微粒(非介子)，其质量为电子的209倍，是一种负电荷，平均寿命为2。

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