DIAGRAM 7.

If it were Black's move he would easily win. In fact he has two
different ways of checkmating White in three moves. One of them
would be to take the Knight with the Rook, attacking the King and
forcing White's Rook to recapture as the King has no square to go
to; then to give check with the Queen on g3 forcing White's King
to h1 and enabling the mate with the Queen on g2 or h2.

The other way would be to start with the check on g3. As White's
Knight is pinned he cannot capture the Queen.

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8 | | | | | | | #K | |
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7 | | | | | | | #P | |
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6 | | | | | | | | |
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5 | | | | | | | | |
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4 | | | | | ^Q | | | |
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3 | | #Q | | | | | ^P | |
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2 | #P | | | | | | | ^P |
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1 | | | | | | | | ^K |
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a b c d e f g h