"He exercises in the morning."
Translation:Lui si esercita alla mattina.
"Lui fa esercizi nel mattino. " is shown as a correct solution. I don't get it why is "nel mattino" and not "nella mattina" ?
I believe mattina/o is one of those nouns that can be masculine or feminine. Like tavolo/a.
An interesting link about 'mattino' versus 'mattina': http://blogs.transparent.com/italian/mattina-o-mattino/
Either way, nella mattina is still not accepted :(
yet according to this blog, if you use "mattina" you can't go wrong? Therefore the problem here is using "nella mattina" instead of "alla mattina"? (Yet "nel mattino" is supposedly a correct solution.) All very mysterious.