Translation:I do not want to pay you for this work.
"Y _ yma" and "Y___ hwn/hon" are all forms of "This". The version using "yma" is easier are you don't need to know the grammatical gender of nouns to use it which is why the course will teach it at first. "Hwnna", "Honna" and are the words for "That" when the object is in sight and become "Hwnnw" and "Honno" when the object is out of sight. The "hwn" words are used with masculine nouns, and the "hon" words are used with feminine nouns. "hyn" is used when no noun is being specified.
Hwn on it's own means 'this' . In written Welsh 'Y gwaith hwn' = this work
For a feminine noun we would use 'Hon'; 'Y sgert hon' = this skirt
In spoken Welsh for simplicity we use 'yma' for both genders.
This work = Y gwaith yma (literally = The work here) = 'This work'
This skirt = Y skirt yma (literally = The skirt here) = 'This skirt'
Just to add to what the others have written...
hwn, hon, hyn can also be used to say 'this one'
- Edrycha ar y beiciau 'ma... beth wyt ti'n meddwl o hwn? - Look at these bikes... what do you think of this one?
- Dw i'n ysgrifennu llythyr i'r papur lleol. Beth wyt ti'n feddwl am hyn..... - I'm writing a letter to the local paper. What do you think of this one... [and starts to quote some phrase from it]
- O, dyma gathod bach braf... wnawn ni ddewis hon? - Oh, these are fine kittens... shall we choose this one?