Explanation please: why is is “ dhà” here and not “dà”?
The number 2 on its own is dhà.
Dhà triggers lenition to nouns following it and loses its own in the process (think of it as passing the h along). So dà chàr.
You've answered the question I just asked on the previous task, thank you!
Why is it Tha mi ag iarraidh and not Feumhaid mi ag iarraidh?
Feumaidh mi... means "I need.." in English :)
Yes, thank you. It occurred to me about 15 minutes after I posted and boy did I feel dumb.