What would these chords be used for? When would you play these chords?
You can play this where it fits, i.e. anytime you are going from 1 to 4 in a song.
What do you mean by passing chord?
Passing / filler chords are just chords that are thrown in here and there to fill in the spaces between the important chords, or the chords that have to be played. Usually, the important chords are the chords you play with the words of a song. The passing / filler chords are the chords in between the words when people are adlibing with stuff like "ohhh, yeaaa, etc." They don't have to always be chords, they can also be runs, which are parts of scales. Here is an example using the song "Thank You Lord":
C / G-C-E
Thank (important chord)
E / G-B-D
You (important chord)
A / E-G-C
Lord (important chord)
A / E-A-C#
*passing / filler chordB / F-Ab-B-D
*passing / filler chordC# / G-Bb-C#-E
*passing / filler chordD / A-D-F
Thank (important chord)
F# / F#-A-C-E
You (important chord)
G / F-G-C-D
Lord (important chord)
G / F-G-B-D
*passing / filler chordRun w/both hands: F, E, D, C
*passing / filler runB / A-D-F
Thank (important chord)
E / G#-C-D-G
You (important chord)
A / G-B-D
Lord (important chord)
A / E-A-C#
*passing / filler chordB / F-Ab-B-D
*passing / filler chordC# / G-Bb-C#-E
*passing / filler chordD / A-D-F
IE / G-C-E
justF / F-A-D
want toD / F#-A-C-E
thankG / F-G-B-D
You/ C
LordTurnaround (chords to get back to beginning):
F / E-A-C
*passing / filler chordE / D-G-C
*passing / filler chordD / F-A-C
*passing / filler chordC / E-G-C
*passing / filler chordE, F, F# /
*passing / filler runG / F-A-C
ohhh *passing / filler chord(repeat)
Now, take a close look at the song. You see where the important chords are, they are the chords with the words. Now, do you see how much space is between the words? Insteading of just sitting there doing nothing, you can play passing / filler chords to occupy those spaces. Do you understand that? If not, I'll keep explaining until u get it.