These are the chords to Summer by Calvin Harris. 

                       C     G     D
When I met you in the summer
                Am     Bm     C
To my heartbeat sound
            C     G     D
We fell in love
                     Am     Bm     C
As the leaves turned brown

               C     G     D    
We could be together baby
                      Am     Bm     C
As long as skies are blue
             C      G     D
You act so innocent now
                Am     Bm     C
But you lied so soon
When I met you in the summer


Then it just repeats. The rhythm is something like two strums on the C and G, then 
one strum on the D, two strums on the Am and Bm and one on the C.