Just as we can use non harmonic notes in a chord, we can do a similar thing among chords.

Besides a neighbor tone there can be a neighbor chord

Besides a passing tone, there can be a passing chord

Besides a suspension, there can be a suspension chord

We discuss three forms connected with the main triads of I, IV and V

 

I64-V-I (the suspension 64 chord)

64-001.jpeg

 

I-IV64-I (the neighbor 64 chord)

64-002.jpeg

 

I-V64-I6 or I6-V64-I the passing 64 chord

64-003.jpeg

 

I-V43-I6-V43-I the passing 43 chord

64-004.jpeg