Translation:Το ασθενοφόρο είναι στον δρόμο.
A Greek would most likely say "Το ασθενοφόρο έρχεται," which the program returned as an incorrect answer. As for the original question, doesn't "The ambulance is on its way." sound more natural?
Thank you. I have added: "Το ασθενοφόρο έρχεται." "The ambulance is on its way." is already one of the accepted translations.