Nimzo-Indian - three knights - Korchnoi variation
1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Nf3 c5 5. d5
White advances the queen's pawn to d4. Black develops the knight to f6. White plays the c-pawn to c4.
Black advances the king's pawn to e6. White develops the knight to c3. Black develops the dark-squared bishop to b4.
White transfers the knight to f3. Black moves the c-pawn to c5. White pushes the queen's pawn to d5.