Things are heating up in here.. We're starting to take clothes off I see.
Or, to be a spoilsport here, the shirt is a gift and he opens the wrapped package (especially if it is one of many he received).
Thanks for being a "spoilsport"!
He must be a lucky guy, so many gifts :-)
Sometimes Duo has the weirdest sentences (seen from an ESL perspective). If I think of a shirt, it normally hasn't buttons or zippers.
"Ele abre o casaco" would have been clearer.
Why can it not be 'he spreads the shirt'? For instance, spreading the shirt on the table, spreading the shirt on the floor etc