Suspended chords create the sound of suspense. They will appear like modified versions of chords you already know, and the way they are typically used is that a suspended chord resolves to its non-suspended version. (For example, Asus2 usually goes to A.)
Notice how similar the chords Dsus2 and Dsus4 appear to our original D chord, as well as the A and G variations on this page. Usually only one note is changed from the original non-suspended chord.
Practice the following chord progressions, and listen for the suspense and then the following resolution, creating a sense of repose or finality to the music.
Asus2 to A
Esus4 to A
Dsus2 to D
Dsus4 to D
Esus4 to E
Gsus4 to G
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And some longer chord progressions inspired by real songs:
Dsus4 to D to Dsus2 to D
Asus4 to A to Asus2 to A
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