约定俗成

The wrong use of the word is sanctioned by usage.

这词的误用已约定俗了。

Traditional identification as to the three styles in singing performance has been tostada in the development in music arts.

约定俗的“三种唱法”划分模式已越来越不利于声乐事业的发展，它缚了人们对声乐这门艺术的艺术性和思想性的认识和表现。