[%c_effect f5;square;f5;type;Interesting;persistent;true] An interesting move, changing the pawn structure.
1. c2c4  1... e7e6  2. g2g3  2... d7d5  3. f1g2  3... g8f6  4. g1f3  4... f8e7  5. e1g1  5... e8g8  6. d2d4  6... c7c6  7. b1c3  7... a7a5 A curious move that is quite popular these days. The pawn advance can be useful in case of a plan with ...b6-Ba6. 8. f3e5  8... b8d7  9. c1f4  9... f6h5 A typical idea: the knight attacks the bishop and then goes back. 10. f4e3  10... h5f6  11. h2h3 Of course White is in no mood to repeat moves. 11... d7e5 [%c_effect e5;square;e5;type;Inaccuracy;persistent;true] The wrong plan of action. 12. d4e5  12... f6d7  13. f2f4  13... b7b6  14. c4d5  14... c6d5  15. e3d4  15... c8a6  16. f1f2 Preparing e2-e4. 16... d7c5 