First language and mother tongue are overlapping concepts. It is the language identity of a nation or an individual that determines the mother tongue, but not the sequence of acquisition.
第一语言与母语是交叉概念，决定母语的不是语言获得的顺序，而是民族或自己的语言认同。
First language and mother tongue are overlapping concepts. It is the language identity of a nation or an individual that determines the mother tongue, but not the sequence of acquisition.
第一语言与母语是交叉概念，决定母语的不是语言获得的顺序，而是民族或自己的语言认同。
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