Numbers 1 is the eighth skill in the Welsh language tree. It has two lessons, and it teaches the decimal numbering system of Welsh and how it works with plurals.

Grammar NotesEdit

Numbering SystemsEdit

Welsh has two numbering systems, one based on powers of ten (decimal) and one based on powers of twenty (vigesimal).

The decimal system is the simplest, as we are already use this system in English. For numbers bigger than ten, the form is x tens and y units i.e. un deg tri is "thirteen" (one ten three).

The vigesimal system is not covered in this course, but you can view it on Wikipedia here.

Plurals with NumbersEdit

When you are using a number with a noun, the noun is not made into a plural, against all logic. The other way this can work (that is not usually permitted on Duolingo) is to use o and the plural form of the noun. So "two dogs" is either dau ci or dau o gŵn.

Dropping LettersEdit

When pump and chwech come before nouns, they are instead pum and chwe.


Lesson 1Edit

  • un = one
  • dau = two
  • tri = three
  • pedwar = four
  • pump = five
  • chwech = six
  • saith = seven

Lesson 2Edit

  • wyth = eight
  • naw = nine
  • deg = ten
  • un deg un = eleven
  • un deg dau = twelve
  • un deg pump = fifteen
  • desg = desk


Duolingo Lesson: