How will the queen be lost anyway here?
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Sign up to join this communityThe correct statement that the book should make is that white either loses the queen or gets checkmated. After black's 3rd move, white has five moves (in algebraic notation, no particular order): 4.Kd4, 4.gxf4, 4.Ke2, 4.Kf3 and 4.Kf2
In case of 4.Kd4, black will checkmate the white king after 4...Bg7+, since the king has no flight squares available.
In case of gxf4, black can recapture on f4 with either queen or bishop, both captures will win white's queen on d2 after the white king has to move (although capturing with the queen wins white's queen without giving a bishop for it)
In the other three cases, black is able to move their pawn so that white's king is in check, while white's queen is attacked by the bishop on h6. I leave it to you to determine which pawn move for black wins the queen in each remaining case.