Queen's Gambit Declined Slav - Semmering variation
1. d4 d5 2. c4 e6 3. Nf3 Nf6 4. e3 c6 5. Nbd2 Nbd7 6. Bd3 c5
White advances the queen's pawn to d4. Black advances the queen's pawn to d5. White advances the c-pawn to c4.
Black pushes the king's pawn to e6. White develops the knight to f3. Black develops the knight to f6.
White pushes the king's pawn to e3. Black advances the c-pawn to c6. White transfers the knight to d2.
Black moves the knight to d7. White develops the light-squared bishop to d3. Black pushes the c-pawn to c5.