I assume you mean what do we play against 1.d4 and 2.c4. It is only a Queen's Gambit if Black plays 1...d5. 1.d4 Nf6 2.c4 is NOT the Queen's Gambit. It is unknown until more moves occur. 2...e6 3.Nc3 Bb4 is a Nimzo-Indian, 2...e6 3.Nf3 b6 is a Queen's Indian, 2...e6 3.Nc3 d5 transpose to the Queen's Gambit Declined. 2...g6 3.Nc3 d5 is a Grunfeld, etc.
That said, none of my games as Black are Queen's Gambits.
Against 1.d4, I play 1...e6 and now:
2.c4 f5 is a Dutch
2.Nf3 f5 is a Dutch
2.g3 f5 is a Dutch
2.e4 d5 is a French
2.Nc3 Bb4 and now 3.Bf4 gives White a bad version of either the Jobava or Barry Attack, depending and 3.e4 d5 leads back to the French Winawer
2.Bf4 f5 gives White a bad version of the London System, specifically known as the Dangerfield Attack.
No Queen's Gambit on my board when I'm Black.
What do you play against the Queen's Gambit as Black?
I am wondering what other people play against this opening.
I will wait until July 2nd and post the results and a new forum!