"When do you arrive tomorrow?"
Translation:Quando arrivi domani?
Yes, that is what I put too...I am getting really frustrated with DL's restrictions on the use of the pronoun subject, or not!!!
It might be more correct to say "Quando arrivi domani" but surely "Quando tu arrivi domani" is not worng
Duolingo did not accept this, which was my response. It seemed more precise to me in terms of the question, and, given "Lotha"s remark below, I still prefer it.
It is more correct to omit the "TU", just: "Quando arrivi domani?" (meaning the exact hour you get there)