1·There is now a single accepted pronunciation for the vast majority of words in ordinary polite use, deviation from which is regarded either as a provincialism or as a vulgarism.
现今日常社交所用的大多数读音已有了一个公认的统一的标准。不符合这个标准，就被称为方言或俗语了。
2·The word belonged to provincialism, but it made its way into standard speech.
这个字原来是属于方言，后来变成标准语言了。
3·The word is a provincialism, but has made its way into standard speech.
这个字原来是方言，后来变成标准语言了。
4·There is now a single accepted pronunciation for the vast majority of words in ordinary polite use deviation from which is regarded either as a provincialism or as a vulgarism.
现在日常社交所用的大多数词汇有了一个公认的发音标准。不符合这个标准就被称为方言或粗俗的发音。这个句子将一个非限制性定语从句拆译了。