i hear the voices when I'm dreaming

I'm confused, welshwise.

Dydy Owen ddim eisiau pannas = Owen doesn't want parsnips.
Mae Owen eisiau pannas = Owen wants parsnips
Ydy Owen eisiau pannas? = Does Owen want parsnips
Mae Owen yn bwyta/hoffi pannas = Owen eats/likes parsnips

I haven't figured out why eisiau doesn't require the yn that other verbs do -- but the (d)ydy/mae thing is throwing me off. (First person seems to use dw for both; second person uses dych and I don't know if there's an alternate; and I forget all the plurals.)

As much as I like duo's use of phrases and sentences rather than memorizing charts, sometimes it drives me absolutely batshit.

ETA -- per Wikipedia, the verb meaning to-be inflected for tense and, in present/past, has special interrogative and negative forms. Still want a chart though.

Also per Wikipedia, yn is the equivalent of -ing, wedi makes it perfect (so I guess Mae Owen wedi hoffi pannas = Owen liked parsnips, whereas Roedd Owen yn hoffi pannas = Owen was liking parsnips, or something) but that doesn't explain why eisiau doesn't use yn/wedi/newydd...

ETA 2 -- per reddit (lol), yn/wedi/newysd are aspect markets that apply to most verbs, but eisiau, which is also spelt isio, is an exception. Which makes me feel oddly better. (Apparently it's not really a true verb, and the 'proper' construction would be equivalent to "the desire for whatever is at me", so it's just a special snowflake.) and the ydy/mae forms I've put in a comment on this entry.