what is the difference between dearg and rua?
rua is used for hair and fur and such.
I see, so it's like the sort of difference there is between yellow and blond?
I see! Thank you :)
Could i use "buí 'is dearg" in this case.
While is probably developed as a contraction of agus, you don't need to use an apostrophe to indicate that - you'd just write buí is dearg. (Though I don't know if Duolingo will accept is for agus everywhere).
Go raibh maith agat. Not accepted yesterday.