Sorry to be a whiner, but I have to say I'm not a fan of surnames being used in the names (especially 'Lingo' Im afraid). It makes it a bit clunkier to type the answers when zipping through.
excuse me but I is welsh and we does say "fyddet ti'n" so what goin on ?
Its local dialect (tafodiaith) that isn't used in all areas of Wales. While its correct in your area, it is unfortunately bad practice to teach learners ways of speaking that aren't the 'national standard' even if it sounds more natural to do so.
That's fair enough, I guess I'm not likely to write any grammar books any time soon.
I tried, 'fyddi di Ceri Lingo yn ffonio?' This was incorrect, but I could do with an explanation as to why. I thought we could use sentence order for emphasis here?
In some sentences you can move the subject around for emphasis yes, but that does not work in this instance. Your suggestion would translate to "Will you, Ceri Lingo, be phoning?"