2959c81e_ufficient_Mating_Material_Rule__2
[0] Example F [2] 
Black to move. This setup is drawn, because there is no way to end the game in mate. Black can't avoid white's stalemate, so the game would end in stalemate. White's last move was Qg7+. Black now would have to take the white queen to escape from check either by Kxg7, Rxg7 or Nxg7, and after that the result would be stalemate, so the game can't end in mate. This is why the game is drawn in this position according to the rule at the top of this page. Anyway this is a good example to show how white can save a half point from a lost position. Black has massive material advantage, and could easily win the game, if white didn't move Qg7+. With this move the game is drawn, regardless how strong black is.
[E4EC] The insufficient Mating Material Rule
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