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

For box 6, Number 1 is only possible in cell (9,5)

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

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

Number 3 is the only value possible in cell (2,5).

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

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

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

For column 6, Number 4 is only possible in cell (6,2)

For row 4, number 2 is only possible in cell (5,4)

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

For column 6, Number 5 is only possible in cell (6,8)

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

For box 9, candidates for 2 are all in row 8, so you can remove candidates from other blocks.

For box 4, candidates for 1 are all in column 2, so you can remove candidates from other blocks.

For box 4, candidates for 8 are all in column 2, so you can remove candidates from other blocks.

Naked Pair for 1 and 4, can remove these as candidates from other cells.

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

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

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

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

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

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

Number 8 is the only value possible in cell (3,2).

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

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

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

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

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

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

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

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

For row 7, number 3 is only possible in cell (8,7)

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

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

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

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

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

Number 9 is the only value possible in cell (8,2).

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

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

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

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

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

Number 8 is the only value possible in cell (2,4).

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

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

Number 8 is the only value possible in cell (5,6).

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

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

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

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

Number 9 is the only value possible in cell (5,8).

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

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

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

Number 2 is the only value possible in cell (9,8).

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

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