How do i say thank you very much in welsh?

There are a few ways to say "thank you very much" in Welsh, depending on the level of formality and emphasis you want to convey. Here are some options:

Formal:

* Diolch yn fawr iawn - This is the most common and polite way to say "thank you very much".

* Diolch yn fawr iawn i chi - This adds a touch of formality by directly addressing the recipient.

Informal:

* Diolch yn fawr - This is a more casual way to say "thank you very much".

* Diolch o galon - This literally means "thanks from the heart" and expresses a sincere appreciation.

You can also use the phrase diolch am bopeth which means "thank you for everything".

The best choice will depend on the context of your conversation.