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

For column 5, Number 2 is only possible in cell (5,9)

For column 7, Number 2 is only possible in cell (7,6)

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

For row 1, number 4 is only possible in cell (6,1)

For row 7, number 5 is only possible in cell (8,7)

For row 1, number 8 is only possible in cell (2,1)

For box 4, candidates for 7 are all in column 1, so you can remove candidates from other blocks.

For box 6, candidates for 4 are all in column 8, so you can remove candidates from other blocks.

For box 4, candidates for 6 are all in column 2, so you can remove candidates from other blocks.

Number 1 is the only value possible in cell (2,3).

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

Number 9 is the only value possible in cell (1,2).

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

For row 1, number 3 is only possible in cell (4,1)

For column 4, Number 6 is only possible in cell (4,3)

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

Number 7 is the only value possible in cell (5,3).

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

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

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

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

For box 7, candidates for 1 are all in row 9, so you can remove candidates from other blocks.

Naked Pair for 6 and 7, can remove these as candidates from other cells.

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

Naked Pair for 1 and 9, can remove these as candidates from other cells.

Hidden Pair for 5 and 6, can remove other candidates from these cells.

For row 5, number 2 is only possible in cell (6,5)

For row 4, number 2 is only possible in cell (2,4)

Either candidate for cell (8,5) forces 5 into cell (2,8).

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

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

Number 4 is the only value possible in cell (2,6).

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

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

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

Number 1 is the only value possible in cell (4,6).

Number 9 is the only value possible in cell (4,5).

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

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

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

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

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

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

Number 1 is the only value possible in cell (8,5).

Number 3 is the only value possible in cell (1,6).

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

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

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

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

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

Number 6 is the only value possible in cell (3,1).

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

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

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

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

Number 4 is the only value possible in cell (1,9).

Number 1 is the only value possible in cell (3,9).

Number 5 is the only value possible in cell (4,9).

Number 8 is the only value possible in cell (6,9).

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

Number 7 is the only value possible in cell (8,9).