For row 7, number 9 is only possible in cell (4,7)

For row 1, number 9 is only possible in cell (5,1)

For row 4, number 5 is only possible in cell (8,4)

For row 6, number 5 is only possible in cell (3,6)

For column 2, Number 6 is only possible in cell (2,5)

For column 5, Number 2 is only possible in cell (5,8)

For column 5, Number 6 is only possible in cell (5,4)

For row 9, number 4 is only possible in cell (1,9)

For row 9, number 9 is only possible in cell (3,9)

For row 5, number 9 is only possible in cell (1,5)

For column 1, Number 2 is only possible in cell (1,4)

For column 2, Number 4 is only possible in cell (2,3)

For box 4, candidates for 1 are all in row 6, so you can remove candidates from other blocks.

For box 7, candidates for 1 are all in row 8, so you can remove candidates from other blocks.

For box 7, candidates for 7 are all in row 8, so you can remove candidates from other blocks.

Number 3 is the only value possible in cell (7,8).

Number 8 is the only value possible in cell (7,4).

For row 2, number 8 is only possible in cell (9,2)

For box 7, Number 3 is only possible in cell (2,7)

Number 8 is the only value possible in cell (6,7).

For row 6, number 8 is only possible in cell (2,6)

Number 3 is the only value possible in cell (3,5).

Number 7 is the only value possible in cell (3,2).

Number 3 is the only value possible in cell (1,3).

Number 1 is the only value possible in cell (1,6).

Number 7 is the only value possible in cell (1,8).

Number 1 is the only value possible in cell (2,8).

Number 8 is the only value possible in cell (3,8).

For row 5, number 8 is only possible in cell (4,5)

For column 8, Number 3 is only possible in cell (8,2)

Number 1 is the only value possible in cell (5,2).

Number 6 is the only value possible in cell (4,3).

Number 7 is the only value possible in cell (6,3).

Number 1 is the only value possible in cell (8,3).

Number 5 is the only value possible in cell (4,8).

Number 4 is the only value possible in cell (4,2).

Number 3 is the only value possible in cell (4,1).

Number 5 is the only value possible in cell (6,2).

Number 2 is the only value possible in cell (7,2).

Number 1 is the only value possible in cell (4,4).

Number 3 is the only value possible in cell (9,4).

Number 4 is the only value possible in cell (6,5).

Number 7 is the only value possible in cell (7,5).

Number 4 is the only value possible in cell (7,1).

Number 7 is the only value possible in cell (9,1).

Number 2 is the only value possible in cell (8,5).

Number 1 is the only value possible in cell (9,5).

Number 3 is the only value possible in cell (6,6).

Number 7 is the only value possible in cell (5,6).

Number 4 is the only value possible in cell (9,6).

Number 7 is the only value possible in cell (8,7).

Number 2 is the only value possible in cell (9,7).

Number 6 is the only value possible in cell (6,8).

Number 3 is the only value possible in cell (5,9).

Number 1 is the only value possible in cell (6,9).