Ok, Phanit, I can tell you what R.P. means. The letters 'R.P.' stand for 'Received p___unciation' and here 'received' is used as an adjective to describe p___unciation, but really what it means is how 'middle class' people speak in southern Britain.

So, for example, I have an 'R.P.' accent - I don't have a Scottish accent, a Welsh accent, a Northern Irish accent, an accent that defines me from a particular town or region. I have the accent that is, generally speaking, largely from southern England, southern Britain, and it's a class reference as well, it's how middle class people speak.
You hear it a lot on the World Service. Does that answer your question?

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