"No, I want pasta."

Translation: Nac ydw, dw i eisiau pasta.

[dewierwan]

"Nadw" should also be correct here, once again, ignoring the fact that people in the north say things differently.

[azalea28]

Agreed

[Linguatron]

But this is for the South Wales dialect.
You can tell because of the pronunciation of 'u'.

[dewierwan]

The point is that both the South Walian and North Walian dialects should be accepted. I'm not sure what you're on about with regards to the "u", I assume the fact that "eisiau" isn't "isho" as it would be written and said verbally.

[Linguatron]

In North Wales 'u' is pronounced as a close central unrounded vowel (ɨ) and in the South it is a close front unrounded vowel (i).

[DesertGlass]

is there a reason why this isn't dw i'n eisiau ?