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.
A numbered set of appointed readings for a Sunday in the time after Pentecost, keyed to the calendar date rather than to a season. Proper 20, for instance, is the Sunday falling between September 18 and 24.
In Church year — Seasons, festivals, and the calendar that orders them.