"I am going to stay."
Translation:Dw i'n mynd i aros.
When expressing "Going to" in English we use "Mynd i" in Welsh so "Dw i'n mynd i aros" (I'm going to stay", "Dw i'n mynd i Ffrainc" (I'm going to France) and "Dw i'n mynd i fynd i Ffrainc" (I am going to go to France).
But isn't the "to" part included in aros anyway? I thought aros was "to stay"? If i were going to learn Welsh, would it also be "Dw i'n mynd i dysgu cymraeg"?
I tend to think of them as different 'to's. One is an infinitive marker, the other is a preposition used with "to go" to form the future aspect. And yes you are correct except "i" causes a soft mutation so "Dw i'n mynd i ddysgu Cymraeg".
As explained earlier, the i here is attached to mynd, not to aros.
mynd i... has a sense of ‘going to (somewhere)’ or ‘going to (do something)’.
Many Welsh verb-nouns take on a particular meaning when followed by particular prepositions.
I tried Dw i am aros , but Duolingo did not accept it.
Can't am + verbnoun replace yn mynd i + verbnoun in this sentence?
Yes, in some contexts in some dialects. It is not very widely used, though, and not generally taught on introductory courses. There was an example which had popped up in one of our examples, but it has now been removed in order to avoid confusion.