“I wanted” in Course 1 (North/South): “Wnes i isio/moyn”;
in Level 1: “O’n i isio/moyn”.
Can anyone shed light on the difference here?
Just starting to use this Forum - it’s extremely informative and, more importantly, FUN (which is of course the best way to learn).
Diolch
O’n i’n is when you want to refer to something that you did repeatedly over a period of time - I find it helpful to think of it as ‘I used to…’ or ‘I was’ - so ‘When I was a child I used to eat snails’ - Pan on i’n plentyn on i’n bwyta malwod.
Wnes i is for something that you did and then stopped doing: ‘I bought a new coat’, Wnes i brynu côt newydd.
So they can be mixed in the same sentence: On i’n cerdded lawr i stryd pan wnes i weld i tîm rygbi Cymru; I was walking down the street when I saw the Welsh rugby team.
(Edited because English spellcheck)
That sounds weird to me. It’s not something I think I would ever say.
No, I’m certain you wouldn’t. Isio (and I’d guess moyn too) is always felt to be a continuing state (to a Welsh ear, at any rate!) - so you’ll never hear it with ‘wnes i’. Just one of those things that becomes natural via exposure… 
This is something I’ve been struggling to get my head around too. My understanding is:
‘Wnes i’n cerdded i’r pub" = I walked to the pub (a singular, one time action)
“O’n i’n cerdded i’r pub” = I walk to the pub/ When I go to the pub I walk there
I would like to know how you would say ‘I used to walk to the pub [but now someone gives me a lift]’? Is it something like:
"o’n i’n cerdded i’r pub, ond dim [anymore]’ ?
That’s right.
Nope, that would be ‘dwi’n cerdded i’r pyb’. The best approximation for ‘o’n i’n cerdded’ is ‘I was walking’.
I used to walk to the pub (to emphasise it, to make the same point about it being a regular even that is now finished) would usually be ‘o’n i’n arfer cerdded i’r pyb’…
Thank you that does make sense! so you could also day 'O’n i’n arfer chwarae rygbi" for ‘I used to play rugby’
So, would you also say 'Dw i’n cerdded i’r pyb" if it is current [eg you are talking to someone on the 'phone] or would you need to add ‘ar hen o bryd’?
Yes, absolutely…
Yes, that’s fine - you could add ‘ar hyn o bryd’ if you wanted to make it absolutely clear, but you’d probably only do so if you thought there’d been a misunderstanding, in most cases…
Wow…Diolch i chi pawb. Thanks to all for the feedback. I’ve just started to use this Forum. I had no idea quite how interesting it would be.
I hope that eventually I’ll be able to give my own feedback as well as just ask! One step at a time…
Diolch pawb, thank you for sharing all this!
Is it about the “yn” then, to show continuous action?
No, not quite.
“On i’n”, although it’s not too obvious, involves one of the many variations of the verb “to be” which is “bod” in its dictionary form in Welsh.
In this case, it’s really “roeddwn i’n”, which you might write, but most people would say “o’n i’n”.
The “yn” is needed to link the “bod” part (i.e. the “roeddwn”) to the second verb (e.g. “chwarae [rygbi]”, or it could link to an adjective or adverb (I think).
However, “wnes i” doesn’t involve “bod” at all, because “wnes” is actually the short form of the verb “gwneud” (“to do” or “to make”), and it’s only “bod” (in its many variations) that needs that connecting “yn”.
I hope that’s approximately correct, anyway. 
Quick question : you said this about Dw i’n cerdded i’r pyb. Yet, in the challenges we get tafarn for the English word pub. Is pyb actually OK or is it Wenglish? Or is it an invader with sights of a takeover bid?!!! 
You’ll hear tafarn and pyb - pyb is a loanword, of course, but I’m not aware of any reliable way to measure where a word is on the long, slow journey between languages…
I guess, if heads don’t turn, it’s pretty much joined the Geiriadur!!
p.s. Your comment about scottish shops in another thread had me rolling with laughter!! 