The correct way to find the key to a piece of music is to use a pitchfork. Agitato is a state of mind when one's finger slips in the midle of playing a piece of music. Refrain means don't do it. A refrain in music is the part you'd better not try to sing. I know what a sexist is, but I'd rather not say.
Most authorities agree that music of antiquity was written long ago.
My favorite composer was opus. Agnus Dei was a woman composer famous for her church music. Henry Purcell was a well-known composer few people have ever heard of. Johann Sebastian Bach wrote a great many musical compositions and had a large number of children. In between he practiced on an old spinster which he kept up in his attic.