For example, when a woman in a wheelchair was waiting near the communion rail, a parishioner jumped up and quickly moved forward to open the swinging communion rail doors for the priest to leave the sanctuary and give her communion. Because his hands were full holding the chalice and consecrated bread, the priest could not open the swinging doors, nor would he allow himself to do so, because he is holding Our Lord in his hands and would not want to dirty them. So there was a brief moment of what to do, what to do.
Everyone has a Missal and silently prays the Mass with the priest. The Missal is in Latin and English, and I read everything in English before Mass so I can read it in Latin during Mass. The altar boys say the responses. In Latin, they say to the priest, “May almighty God have mercy on thee and, having forgiven thee thy sins, bring thee to life everlasting.” The priest says the same thing to the altar boys. It all gets easier for everyone with practice.
IHS, which you see when the vestments are laid out, is a monogram or symbol for the name Jesus. The letters are a contraction of the Greek word for Jesus, which in Greek is spelled IHΣΟΥΣ.
A genuflection is made every time one passes the tabernacle out of respect for Christ within. There is a good linguistic reason for saying the Holy Ghost. The name comes from the German, Heilige Geist, which means Holy Ghost.
My warm-up explanation has not been reviewed by anyone else. I did my best.