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A B C D E F G H

Diag. 11

Here, too, there is a flaw in the simple calculation, because the
defending units are not secure. Beginners should devote special
attention to this position, which is in practice of frequent
occurrence.

It can be easily perceived that the Bishop cannot capture the
pawn at B7 on account of P-QR3. But to take with the Knight would
also be an error, because Black would then keep chasing away the
covering Bishop.

1. P-Kt4; 2. B-Q6, K-B3; 3. Kt-K8, B-B2; and wins one of the
pieces.

Finally, one more example, in which one of the defending pieces
being pinned makes simple calculation impracticable.

In Diagram 12 it seems at first sight as if Black could play
KtxP: although White can pin the Knight with R-K1

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8 | #R | | #B | | #K | | | #R |
|---------------------------------------|
7 | #P | #P | | | | #Kt| #P | #P |
|---------------------------------------|
6 | | | #P | #Kt| | | | |