To say 'last month' in Welsh we say 'fis diwethaf'. Remember we mutate 'mis' because it's an adverb of time. And 'last week' in Welsh is 'wythnos diwethaf'.
However, we don't use the same construction when we want to say 'last year'. Instead, there is one specific word - 'llynedd' which means 'last year' - 'llynedd'. Similarly we have just the one word when we want to say 'this year' - 'eleni' - 'eleni'.
Whoever said that two words were better than one?!
Jac thinks that Agnes might not love him anymore and seeks reassurance. He checks with her that she hasn't changed her mind about him and that she hasn't started to reconsider:
Dwyt ti ddim wedi dechrau ail-feddwl?
Literally this means, 'You haven't started to second-think?'
We often translate the English prefix 're-' as in reconsider or rewind, with the word 'ail', which is the ordinal number meaning 'second'.
Here are some examples:
Ail-wneud - to re-do Ail-gylchu - to recycle Ail-adrodd - to repeat
Brian has collected some old boxes and old wood to put on Rhodri's 'coelcerth' - bonfire.
Dim ond wedi dod a rhyw hen focsys a rhyw hen goed i'w rhoi ar y goelcerth ydw i.
Note that the adjective 'hen' meaning 'old' unlike most other adjectives in Welsh usually precedes the noun. The noun must then be followed by a soft mutation.
Hen goed old wood or old trees Hen focsys - old boxes
Similar examples are: Hen ddyn an old man Hen dŷ - an old house Another adjective that precedes the noun is 'hoff' meaning 'favourite'.