Sorry if this topic has been raised before, but I have noticed as I start getting into reading contemporary Welsh novels not specifically aimed at learners that while the narrative may be written in a fairly regular sort of Welsh, the dialogue (which I assume to be realistic) is often heavily peppered with purely English words simply given a Welsh spelling. This seems particularly true when teenagers are speaking. For example, within the space of a few pages I find blwmin, blincin, boncyrs, feirws, brên, miwsig, prat, crap, cym on, fflipin, stwpid, stwbwrn, absoliwt, bisâr, bêb, sili and hangover (surely the Welsh must at least have their own word for hangover!). Is there any way of knowing, other than by long experience, which of these anglicisms are an accepted part of the modern language and which are going to make you sound a bit of a wally? Is it best to steer well clear of them or conversely, if you always try to stick to native Welsh words, are you going to sound a bit stilted or affected? Is ‘cerddoriaeth’, for example, the perfectly neutral proper word for ‘music’ or is it being ousted in speech by ‘miwsig’? Would a careful speaker always use ‘ymennydd’ rather than ‘brên’? Is ‘ystyfnig’ (or ‘styfnig’) now a bit literary in speech compared to stwbwrn? And so on.