"Yes, I had dry weather."
Translation:Do, ges i dywydd sych.
This one is for some forms of cael only. If you get hold of a grammar book such as 'Welsh Rules' it will cover some of the variations that are commonly found.
You might find it useful to make some tables of the conjugations of the main irregular verbs - bod, mynd, dod, gwneud, cael - with space to add common variations. There are some clear patterns that emerge, and some exceptions to the patterns. www.gweiadur.com (you will need to register for free) shows conjugation tables of verbs, so you could use those as a starter - stick with the 'informal/anffurfiol' forms of conjugations for now.