I often have people ask me, "Isn't Latin a dead language?" or "Didn't the Church outlaw Latin with Vatican II?"
In reality, nothing could be further from the truth. Yes, Latin is no longer used for everyday conversation, but it's the basis for a large part of our English vocabulary. In fact, even the word "vocabulary" has Latin roots, from "voco", to call or "vox", voice.
And the Catholic Church didn't outlaw Latin. The Vatican II Constitution on the Sacred Liturgy allows the use of the vernacular in portions of the Mass. Sadly, most bishops took that as license to abolish the language. (Of course, Latin is the language of the Roman - or Latin - Catholic Church. Other Catholic Churches in communion with Rome, such as the Ukrainian or Melkite, have never used Latin as a principle language).
So why pray in this language?
1) The saints prayed in Latin
2) The official version of most prayers is still in Latin.
3) The meaning of some prayers is often obscured by poor translations. Take for example the Gloria. The English says, "Glory to God in the highest, and peace to his people on earth." The Latin is "Gloria in excelsis Deo, et in terra pax hominibus bonae voluntatis" - "Glory to God in the highest, and on earth peace to men (or people) of good will". A small difference, but significant.
4) Knowing how to pronounce Latin properly opens up the world of Gregorian Chant, which, as the Vatican II Fathers wrote, retains the pride of place in the Liturgy. In other words, the Church teaches that the principle music in the Holy Mass is, and should remain, Gregorian Chant. Now isn't that preferable to some of the drivel that passes for liturgical music today?