pull down to refresh

1.d4 d5 2.c4
reply
1.d4 d5 2.c4 e6
reply
reply
1.d4 d5 2.c4 e6 3.Nc3
reply
reply
1.d4 d5 2.c4 e6 3.Nc3 b6
reply
reply
1.d4 d5 2.c4 e6 3.Nc3 b6 4.Nf3