约定俗成 | established by convention and custom

yuē约dìng定sú俗chéng成

Established by long-standing convention or common practice; accepted through common usage.

很多日常用语的读音和用法都是约定俗成，没有严格的语法规则。

The pronunciation and usage of many daily expressions are established by common practice; there are no strict grammatical rules.

Era:

Ancient

Frequency:

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