I have this piece from Bach called "no. 35, BWV 514" and there are these ornaments that i don't understand. Like the grace note at bar 11 where there is a eight grace note and a trill notation over the note. I know that the grace note should take half of the value of the principal note, but i don't know how to play it when the grace note has a trill mark.
Then at bar 15 there is a trill but how should it be played and end on the G note without messing the trill up.