Fork

Fork Level Beginner (a)
1) Rd7+ (Rook moves up to square d7 check)     2) Rd7+  (Rook moves up to square d7 check)
3) Re7+ (Rook moves up to square e7 check)      4) Bd5+ (Bishop moves up to square d5 check)
5) Be5+ (Bishop moves up to square e5 check)    6) Be5+ (Bishop moves up to square e5 check)
Fork Level Beginner (b)
1) Ne7+ (Knight moves up to e7 check)               2) Ne6+ (Knight moves up to e6 check)
3) Nf6+ (Knight moves up to f6 check)               4) Qe6+ (Queen moves up to e6 check)
5) Qe8+ (Queen moves up to e8 check)              6) Qa2+ (Queen moves to square a2 check)
Fork Level Intermediate (a)
1) Qd5+ (Queen moves up to d5 check)              2) Qh5+ (Queen moves up to square h5 check)
3) Bd5+ and Rd7+                                              4) Nd6+ (Knight to d6) and Nh4 (Knight to h4)
5) Re5+ , pawn c3  and Be5                                6) pawn b4, Rd5 and Be6
Fork Level Intermediate (b)
1) Qg5 (Queen moves up to square g5)                2) Qc4+ (Queen moves up to c4 check)
3) pawn b4 and pawn e5                                      4) Be5 (Bishop to e5)  and Ke3 (King to e3)
5) Nd7+, Qg3+ and Nf4 (Knight to f4)                 6) pawn b4, pawn d4, Nc4 and Bf6
Fork Level Advanced (a)
1) Qc2+                                                              2) Ng6+
3) Pawn b4                                                          4) Nf6+ (Knight to square f6 check)
5) Rxg6+ (Rook captures pawn on g6 check)       6) Rxf5+ (Rook captures pawn on f5 check)
Fork Level Advanced (b)
1) Bc4                                                                 2) Rd4
3) Qh5+ (Queen moves to h5 check)                   4) Pawn e3
5) Rd1+                                                              6) 1. ... Qxc3 then  2. Qxc3 Ne2+