For row 1, number 1 is only possible in cell (3,1)

For row 9, number 1 is only possible in cell (7,9)

For row 6, number 1 is only possible in cell (9,6)

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

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

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

For row 2, number 3 is only possible in cell (7,2)

For row 4, number 3 is only possible in cell (8,4)

For row 3, number 5 is only possible in cell (4,3)

For row 3, number 8 is only possible in cell (9,3)

For column 6, Number 7 is only possible in cell (6,5)

For column 2, Number 7 is only possible in cell (2,9)

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

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

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

For row 8, number 5 is only possible in cell (9,8)

For box 9, Number 6 is only possible in cell (7,8)

For box 1, candidates for 6 are all in row 2, so you can remove candidates from other blocks.

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

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

Number 8 is the only value possible in cell (6,1).

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

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

For row 7, number 9 is only possible in cell (1,7)

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

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

Number 7 is the only value possible in cell (1,2).

Number 6 is the only value possible in cell (3,2).

Number 8 is the only value possible in cell (1,4).

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

Number 9 is the only value possible in cell (7,4).

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

Number 6 is the only value possible in cell (8,1).

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

Number 7 is the only value possible in cell (3,4).

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

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

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

Number 6 is the only value possible in cell (9,5).

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

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

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

Number 8 is the only value possible in cell (5,7).

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

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

Number 4 is the only value possible in cell (6,8).

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

Number 9 is the only value possible in cell (2,3).

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

Number 4 is the only value possible in cell (2,5).

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

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

Number 9 is the only value possible in cell (3,6).

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

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

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