What is a dialect? 什么是方言？

What is a dialect? A dialect is a different spoken language with an accent. When we clarify languages, we do written languages first. If people use the same written languages, their language is one language, No matter their accents. The spoken language of non-mainstream people is a dialect. As for the spoken languages without written language, as long as you think they are different, they are different languages. There are no workable criterion to clarify spoken languages. So the clarification of spoken languages is sociolinguistics.
Latvian linguistics, Max Weinreich said "A language is a dialect with an army and navy". I prefer "A language is a dialect without a written language, and a dialect is a spoken language with a written language."


Reference: New Concept Linguistics

什么是方言？

方言是一种有不同口音的口语。我们划分语言，首先是按照书面语划分，也就是按照文字划分。使用同一种文字的口语，不论说话带有什么口音，他们说的口语都是同一种语言。非主流口音的口语就是方言。
没有文字的口语，只要你认为不一样，就是不同的语言。没有文字的口语的划分，通常是按照人群划分。所以口语的划分是社会语言学。

拉脱维亚语言学家 Max Weinreich 说“语言就是方言有了军队”。 我认为“语言就是方言没有书面语，方言就是口语有了书面语”。

参考：新概念语言学