Reti accepted - Keres variation
1. Nf3 d5 2. c4 dxc4 3. e3 Be6
White develops the knight to f3. Black pushes the queen's pawn to d5. White plays the c-pawn to c4.
Black captures on c4 with the queen's pawn. White advances the king's pawn to e3. Black develops the light-squared bishop to e6.