On: every psalm and song in the daily prayers uses today’s English. Off: all of them use the older “thee and thou”. Until you choose, the Songs of Zechariah, Mary and Simeon use today’s English, as most churches sing them. The Lord’s Prayer and the prayers for the dying show the form most people learned.
Latin for “three days.” The single liturgy spanning Maundy Thursday evening through the Easter Vigil, understood as one service in three parts rather than three separate ones.
In Church year — Seasons, festivals, and the calendar that orders them.