G - x 10 x 7 8 10

Chord notes: G, D, G, D

This chord works well in the key of G along with these chords:

C - 8 x 0 7 8 10 (Use your thumb for the 8th fret of the E string)

D - 10 x 0 7 8 10

Em - 0 x x 7 8 10