[FEN "r2q1rk1/pbpn1pp1/1p2pn1p/8/1bBP3B/2N1PN2/PP3PPP/R2QR1K1 w -"]

11. e4 Be7


w b wb bw | w b wb bw

w     an
    


11. e4      an
    


11...Be7      an