-ais i / -aist ti / -odd

The endings (prynu, to buy → stem pryn-)

• prynais i I bought
• prynaist ti you bought
• prynodd e (North o) / prynodd hi he / she bought
• prynon ni we bought
• prynoch chi you bought
• prynon nhw they bought

Prynon ni and prynon nhw sound the same; the pronoun tells them apart. Formal writing has longer forms such as prynasom; see Literary Past Endings.

Noun subjects. With a noun subject, use the -odd form, even for plurals: Canodd y plant (The children sang). See Mae With Any Noun Subject.

The object softens. The thing bought or seen, right after the subject, takes soft mutation: Prynais i gar. See Direct Objects After Short Verbs.

In speech the verb is often softened too, because a little word (fe in the South, mi in the North) is understood in front of it: Brynais i gar, Fe brynais i gar, Mi brynais i gar. See Mi (North) and Fe (South) Before Verbs.

Another way. Speech, especially in the North, often uses a past form of gwneud + verb-noun instead: Wnes i brynu car. See Past With Gwneud.

Questions soften the verb and are answered do or naddo: Brynaist ti fara? Do. See Yes and No in the Past and Questions and Negatives of Short Verbs.

For finding the stem, see Finding the Verb Stem; for mynd, dod, cael and gwneud, see Irregular Past.