In Suspended Chords, the 3rd of the chord is replaced by the 4th degree of the scale it is derived from. Because these chords have no 3rd degree, they work equally well in both major and minor keys. Suspended chords often resolve back to a major or minor chord of the same letter name as demonstrated in the following diagram.
Csus
Here are four more common suspended chord shapes and a chord progression to practice them with.
Gsus
Dsus
Asus
Esus