Queen's Gambit Declined - Tarrasch - Prague variation
1. d4 d5 2. c4 e6 3. Nc3 c5 4. cxd5 exd5 5. Nf3 Nc6 6. g3 Nf6
White pushes the queen's pawn to d4. Black advances the queen's pawn to d5. White moves the c-pawn to c4.
Black plays the king's pawn to e6. White develops the knight to c3. Black advances the c-pawn to c5.
White captures on d5 with the c-pawn. Black captures on d5 with the king's pawn. White transfers the knight to f3.
Black develops the knight to c6. White advances the g-pawn to g3. Black jumps the knight to f6.