For row 9, number 7 is only possible in cell (8,9)

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

For row 6, number 7 is only possible in cell (6,6)

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

For row 4, number 5 is only possible in cell (7,4)

For row 1, number 9 is only possible in cell (8,1)

Number 3 is the only value possible in cell (8,4).

For box 7, Number 9 is only possible in cell (1,7)

For column 9, Number 2 is only possible in cell (9,6)

For row 6, number 3 is only possible in cell (2,6)

For row 7, number 8 is only possible in cell (2,7)

For box 5, Number 8 is only possible in cell (4,4)

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

For row 6, number 9 is only possible in cell (7,6)

For column 8, Number 4 is only possible in cell (8,6)

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

Number 4 is the only value possible in cell (3,5).

For box 3, candidates for 3 are all in row 3, so you can remove candidates from other blocks.

For box 9, candidates for 6 are all in column 9, so you can remove candidates from other blocks.

Candidates for 5 in boxes 1 and 3 force the candidates in box 2 to be in the remaining line.

Candidates for 6 in boxes 1 and 4 force the candidates in box 7 to be in the remaining line.

Naked Pair for 2 and 4, can remove these as candidates from other cells.

Naked Pair for 6 and 8, can remove these as candidates from other cells.

Naked Pair for 6 and 8, can remove these as candidates from other cells.

Either candidate for cell (3,1) forces 2 into cell (5,3).

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

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

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

Number 1 is the only value possible in cell (2,4).

Number 2 is the only value possible in cell (1,4).

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

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

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

Number 1 is the only value possible in cell (5,7).

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

Number 6 is the only value possible in cell (2,8).

Number 9 is the only value possible in cell (4,8).

Number 1 is the only value possible in cell (9,8).

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

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

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

Number 6 is the only value possible in cell (1,2).

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

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

Number 8 is the only value possible in cell (6,3).

Number 6 is the only value possible in cell (8,3).

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

Number 1 is the only value possible in cell (7,3).

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

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

Number 6 is the only value possible in cell (9,7).

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

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

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

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

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

Number 4 is the only value possible in cell (2,9).

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

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

Number 3 is the only value possible in cell (7,9).