In music, the term “key” refers to a particular set of notes that are emphasized, thereby giving a composition a particular mood. In the broader realm of music theory, there are many different keys, though the two that are most frequently used – and easiest to hear – are major keys and minor keys. Major keys tend to sound bright and happy; minor keys tend to sound dark and sad. Listening to Vivaldi’s music, try to notice when the music shifts from one of those keys to another. Do those shifts help you to keep track of what seasonal scene is being captured? (Note: just because something is played fast or loud doesn’t mean it’s necessarily happy; also, slow or quiet isn’t always sad.)