Instead of dó, we use dhá for the number two when followed by a nounThe name of a thing such as an object, a place or a person. Nouns are often described as naming words., for example:
two tables - dhá thábla
Instead of ceathair, we use ceithre for the number four when followed by a noun, for example:
four tables - ceithre thábla
To count from 11 to 19, we simply add déag after the first number.