Figure 3.4.3.3[White to move]

Observe White's queen behind the e5 pawn; the formation invites a search for a discovered check. Think of the pawn moving forward and attacking Black’s queen in classic fashion. The obvious hitch is that the path isn’t clear; Black’s e6 pawn is in the way. So go to work to eliminate the obstacle. We customarily remove bothersome pawns by capturing whatever they protect. Here the e6 pawn protects the knight on d5, so White captures it with RxN, inviting e6xR. Now the discovered check e5-e6 is easy, winning the queen with e6xQ or (if the queen moves to f6) NxQ.