Figure 4.2.1.8[Black to move]

Here Black starts with a pin already in place on White’s f3 knight. The knight is well-guarded, and one of its guards is a pawn, so Black has no obvious way to capture it. As usual, though, the goal is to go after the knight with a pawn, and as we saw in the previous position pawns sometimes can march up the board by threatening enemy pieces as they go. Here Black experiments with a threatening push: h7-h6. White has to move his queen—but ask where. Sometimes that question will be easy to answer, as in cases like this where the queen’s range of motion is limited. Here it has to go to h4 or else be lost on the spot. Now what does Black do? Remember the objective: to march a pawn up the board. Black can play g7-g5, again threatening White’s queen. The queen either takes Black’s pawn on h6 or moves to h3. Either way, Black completes the exercise with g5-g4, at last attacking the pinned White knight and winning it a move later.

A few lessons to take away from this study: First and generally, when you have pinned an enemy piece do not give up lightly on the hope of throwing a pawn at it. Pawns are frightening to larger pieces, and this can give them unexpected mobility. Second, a pawn in its starting position is—somewhat surprisingly—only two moves from threatening a piece on the enemy’s third rank. Third, the position shows how pawns sometimes can march up the board together, with one issuing a threat and then providing protection for the other as it too advances.