It doesn't, in other words, derive from an antecedent single cause as an effect.

换句话说，它不是，作为结果来自单一的先行的原因。

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And "Dog" Is also a morpheme, but not always because there are single morphemes and then there are words that are composed of many morphemes.

狗"也是一个语素,但词和语素并不总是相同,因为语素是独立的,但词却可以由很多语素组成

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