Welsh: numerals


Senior Member

I've been learning Welsh for a few weeks now and I'd like to ask native Welsh speakers about the numbers. Which system do people use more often in spoken Welsh, the vigesimal (traditional) or the decimal system? Which one is preferred at Welsh-medium schools?
So, is 20 "ugain" or "dau ddeg"?

Diolch yn fawr.
  • I'm not sure what's taught in schools these days - I imagine probably both, since both are used in spoken Welsh.

    The system you use depends on what you are talking about. Age is usually referred to using the traditional system - for example, I would say "Rwy'n naw ar hugain" (I'm 29). I would use the decimal system for awkward prices such as £1.99 - I would say "punt, naw deg naw", since saying 99 using the traditional system would be a bit of a chore.
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    Thank you for your reply.

    Another question: when I was looking for Welsh-language videos on the net just to "listen into" the language, I came across one where an elderly Welsh speaker repeatedly used English numerals for saying years, in the middle of a Welsh sentence, like "...welsh welsh welsh nineteen sixty-five welsh welsh...".
    How common is this phenomenon? Is this just something that older Welsh speakers do, because they were taught in English-medium schools?
    Yes, that happens too, and is quite widespread, although recently there has been a reaction against it and even a reaction against the new-style numerals. My guess is that eventually we will settle down with the new-style numerals ("dau ddeg" instead of "ugain" etc.) as they are beautifully simple, with the old-style just used in elevated speech.
    The main reason why elderly people use English numerals for larger numbers, prices, calculations etc. is that they were educated at a time when Welsh was barely, if ever, used in the school system and they were therefore taught arithmetic exclusively in English. I'm sure you can imagine that if you'd spent years doing your "times tables" and being required to do all your "sums" in, say, French then you'd be quite likely to find yourself saying things like "OK: that'll be quatre-vingt-seize, please, with the vingt pour cent discount".
    I agree with Wynn's post. But I have to say, this is something you'll hear younger people doing too - it's not just elderly people who use English numerals. People often give phone numbers in English, but with a Welsh accent "Rhif fi di tw ffeif, tw ffeif, ffor sics" (My number's 252546). I think the main reason for this is that they learnt their phone number in English, and they have to stop and think what it is in Welsh. That sounds ok in an informal context, but in a more formal context it can sound a bit uneducated.
    Now that years have been mentioned, what is the standard Welsh system for pronouncing a year number?

    I've heard Welsh speakers pronounce years by saying each number individually, rather than combining the numbers together: e.g., for a year such as 1986 I've heard people say un naw wyth chwech. However, I recall being taught to pronounce years as if they were normal numbers: e.g., mil naw cant wyth deg chwech "one thousand, nine hundred and eighty-six" for "1986".
    Most of the time, you can use both - they are both equally valid.

    There are two situations where you can't say each number individually. Firstly, when you would omit the "19" part of the year in English. So, for example, when you say "the 80s" or "in '86" - you'd say "yr wythdegau" and "yn wythdeg chwech". The second situation is basically all the years from 2000 onwards. Dwy fil (2000), dwy fil a deg (2010) etc. I've never ever heard anyone refer to "dau dim dim dim" or "dau dim un dim". It sounds very odd!
    I was taught the decimal system, if you call it that (had my education in Welsh since the age of 4 - 15).

    So, I prefer, and find it easier to say dau-ddeg-chwech. I tend to say 'un-deg-un' instead of 'unarddeg', and my sister does as well (she's 31).

    From my employment dealing with Welsh speakers on a regular basis, I would say the slightly older generation ( 50 years old and older), use the traditional system far more than we do. It can be a little confusing at times, because we're not used to thinking that way. We have to do a quick sum in our head to know which number they mean. So when someone says pedwar-ar-bymtheg, I have to go 4 + 15 in my head!

    Use whichever system you like, but younger people will understand you better if you use the modern system.
    One more question about years: is it ever obligatory to use a(c) "and" before the last digit? (Assuming that the year has more than two digits total?)

    E.g., do you have to say Mil naw cant a chwech for "1906", or can you omit "a"?

    It depends on the number. For example, 1901-10 all require an a/ac. After that, 1911-1920 require an a/ac only when using the traditional numbering system. So 1911 = mil naw cant ac unarddeg, or mil naw cant un deg un. 1920 = mil naw cant ac ugain, or mil naw cant dau ddeg.

    PS. Regarding Cerinwen's post about the traditional system, I know a lot of people who use it, and I also use it - I'm 29 and hopefully not old yet ;) I don't find that system difficult to understand, except when it gets to larger or less frequently used numbers. 11 to 30 are fine and I hear them used frequently. Once you go past 30 I agree with Cerinwen that they're a pain and best avoided. For example, it would take a minute to process a number such as dwy ar bymtheg ar hugain (37). I would just say tri deg saith.
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