This is a cool, groovy and funky song. It's in chord format but is still very enjoyable.

(G)I was dancing when i was twelve (Em)

(G)I was dancing when i was twelve (Em)

(F) I was dancin when i was aah (C)

(F) I was dancing when in was aah (C)

This verse (with changed lyrics) is repeated a few more times before Marc adds 

a little change on the end, when he goes ooh, ooh, oohooh.

It plays:

(Am) aaah, (D) aaah, (D7) aaah aaah.

This is basically the whole of the verses before Marc Pplays the lead. It is 

simple but very enjoyable. Enjoy! 

R.I.P Marc, Micky and Steve!