Learns to stop a pawn on the seventh rank with the queen.
The enemy pawn is about to promote and your king is far away. Can the queen stop it alone? The method: use checks and pins to force the black king onto b1, in front of its own pawn.
Check the black king with your queen or pin the pawn. Careful: not every move works; the queen must keep control of the promotion square.
The exception: bishop and rook pawns. Here the black king ran to the a1 corner instead of c1. Qxc2 is stalemate! With rook and bishop pawns the defender often draws with this stalemate trick.