有这种说法吧

The study of RP is concerned exclusively with pronunciation, whereas Standard English, the Queen's English, Oxford English, and BBC English are also concerned with matters such as grammar, vocabulary, and style. An individual using RP will typically speak Standard English, although the converse or inverse is not necessarily true. The standard language may be pronounced with a regional accent and the contrapositive is usually correct. It is very unlikely that someone speaking RP would use it to speak a regional dialect.