1. Were you aware that some of those music were composed centuries ago?
Yes, I am very much aware that some music were composed centuries ago. Most where done in Latin due to the fact that, most music that emanated from the church was based in Latin.
2. Were you able to identify the characteristics of Gregorian Chants?
Ability to identify the characteristics of Gregorian Chants lies in the
language adopted in song. Also, the high and low alternate tones is another factor. Example is the Laudant Dominum Song (A Gregorian Chant in Latin)
In common, they all have verism (an extreme or strict naturalism in art or literature). Denarius of Julius Caesar is on a coin, Augustus of Primaporta has a statue of himself and Emperor Justinian is portrayed as a mosaic.
