"He comes at noon."
Translation:Lui viene a mezzogiorno.
IMO "arriva a mezzogiorno" should be accepted. Because I have noted my Italian exchange student says "arrive" for everything. He "arrives to the party", then "arrives home late", "arrives at the finish", "arrives to the answer" (of a maths problem), "arrives to the end of the exam", etc. etc. Arrive (arrivare) seems to be used widely, more than in English.