Mutation query

I came across this in an article: ‘Unwaith eto dôth ddydd Gŵyl Dewi i Gaernarfon. Mi ddôth â thywydd oer iawn eleni, ond unwaith eto dôth Ŵyl Ddewi Arall i Gaernarfon i roi croeso cynnes i bawb’. Can someone explain why in this case there is soft mutation of dydd and Ŵyl after dôth? I know there is SM of a noun object after a short-form verb, but surely in these sentences ddydd and Ŵyl are subjects of dôth, and I can’t find a mutation rule to cover this, though there are so many mutation rules I could well be missing one!


I’m struggling to see any reason for the mutatation too, for the reasons you give. The only possible explanation I can think of is that there’s a hidden e/o/hi (it) functioning as the subject of doth and “ddydd Gwyl Dewi / Wyl Ddewi Arall” are adverbial phrases (“it came on St. David’s Day”), which would require a soft mutation (cf. es i yno ddydd Llun - I went there on Monday).

But it could just as easily be a mistake - not all Welsh speakers are aware of the ‘rules’ and I get the impression that some ‘over-apply’ them.

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As you say Peter, it’s because they are adverbial, but more specifically time adverbs. These usually indicate ‘when’, ‘how often’ and sometimes ‘how long’ an action or event takes place.

1st sentence from me, 2nd sentence courtesy of Gareth King (Modern Welsh: A Comprehensive Grammar p241) :wink:


Diolch, Siaron! Must admit, when I first read the sentences I interpreted them as “St David’s Day came” and was puzzled by the mutation. But as I was typing my first post, the adverbial possibility hoved into view…

But I have seen people applying soft mutations to what is clearly the subject of the verb, which is always confusing (possibly a case of hyper-correction).

Possibly, but one thing to bear in mind is that often written Welsh and spoken Welsh will differ when it comes to mutations - spoken Welsh tends to go with whatever ‘flows’ and sometimes this means mutations are left out from where they should be or added where they don’t need to be. Formal written Welsh (not necessarily high literature stuff) will generally use mutations correctly and they will sometimes appear where you’ve never heard them in speech (or maybe just not noticed - i.e. they ‘stick out’ more when written down!).


Cheers Siaron. I understand your point but I’ve definitely encountered examples of over-zealous mutation. For example, I recall seeing somewhere someone trying to illustrate how the indefinite direct object of a short-form verb mutates by giving a load of examples where the mutated words were clearly and unambiguously the subject of the verb (and so no mutation required). Typically, I can’t find examples right now but if I do, I’ll list them here.

TBH I’m still struggling to see these as adverbs - if they’re adverbial what’s the subject of the verb?

It is a bit difficult Richard. It might help to think of the ‘verby bit’ as ‘happening when/for how long/for how often’ then the ‘ddydd Gŵyl Dewi/ŵyl Ddewi Arall’ are the adverbs that describe happening.

It’s sometimes handy to know these grammar nuggets, but always remember that in speech you’ll barely notice these things - either that they are there (as they often are) or that they are missing (as they often are), so don’t let it give you a headache!

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Hi Richard,

If ddydd Gŵyl Dewi and Ŵyl Ddewi Arall are indeed adverbial phrases (meaning ‘[on] St. David’s Day’, etc), then the grammatical subject of the verb would be a ‘hidden’ e/o/hi (meaning ‘it’).

So the literal meaning of the first sentence would be “It came on St. D’s Day to Caernarfon”.

I managed to locate the original article (with an English translation) here:

I must admit, I still find the syntax of these sentences slightly odd, even after running a grammatical fine tooth-comb over them. It would seem more natural to me to say ‘daeth/dôth dydd Gŵyl Dewi i Gaernarfon (St. David’s Day came to Caernarfon)’ and ‘dôth Gwyl Ddewi Arall i Gaernarfon’ (Another St. D’s Festival came to Caernarfon) - in other words, make the names of the festivals the subject of the sentences (and not mutate them) - but I’m not an expert and it may just be a lack of exposure to different styles of Welsh on my part.

As Siaron says, probably best not to let this kind of thing give you a headache…unless, like me, you enjoy being given a headache by exactly this kind of thing!

Edit: recalling a previous discussion (on ‘ac mae’n’), I may suspect you’re in that category of learner too!

Yes but, no but - I think only posh, literary Welsh is going to be pronoun-dropping, and this didn’t really strike me that way, especially as Neil (sp?) at Parallel has it down at Foundation level or something. I did notice that the writer was in the final rounds of Learner of the Year, so is a presumably very good but not native speaker - so I’m tempted to wonder if it’s actually just a slip (Heaven knows I’m going to continue making egregious errors with mutations and, indeed, basic grammar for years to come!) - only @siaronjames reckoned it to be kosher…

It could be kosher, albeit stylistically odd (as you say, pronoun-dropping is more literary style). But, the more I think about it, the more I’m inclined towards the view that it’s a slip up.

Well, I think it is what I thought it was but I could be wrong. I’m not really an expert - I did fail the module on particularly strict grammar rules when I was at Uni! :wink: