Allegros are fast and happy music.
Allegros are usually fun and make people feel good.
Examples:
The music was an allegro, so we danced fast.
Can you play the allegro on the piano?
She likes to listen to allegros when she is happy.
The allegro made everyone want to dance.
The allegro was so fast, it made my head spin.
I love the allegro because it makes me feel happy.