Yes We Can chords by The Black Eyed Peas

It just keeps repeating, G, B, E, C

the rhythm is like this:

e|-------3-|  x2
b|-------0-|
g|-------0-|
d|-------0-|
a|-------2-|
e|-3--3--3-|

That's just for the G chord, but it's the same for all of them.
Video: http://www.youtube.com/watch?v=BHEO_fG3mm4
After watching the video, you'll get it.