Colloquial expressions and even slang may be found in standard dictionaries but will be so identified.

俗语甚至俚语都可能在标准字典中查到，但是字典中会标明它们的性质。

youdao

I find that many learners have an obsession with slang and idioms, as if repeating some colloquial expressions is going to upgrade how they sound in a language.

我发现很多英语学习者十分痴迷于俚语和习语，好像背诵一些十分口语化的表达方式就可以让他们的口语升级、听起来更加地道。

youdao