This is a thematic move, but rarely played before castling.
1. c2c4  1... e7e5  2. b1c3  2... g8f6  3. g1f3  3... b8c6  4. g2g3  4... d7d5  5. c4d5  5... f6d5  6. f1g2  6... f8c5 One of the main lines of the modern way of playing the English Opening. 7. d2d3  7... e8g8 