This is an example of a completed Tents puzzle. The puzzle starts with a set of horizontal and vertical clues and a grid containing trees.

Your task is to insert tents in the grid so that,

1. Each tree is paired with a tent - the tent must be next to the tree horizontally or vertically.
2. Tents are never placed next to each, including diagonally.
3. The horizontal and vertical clues tell you how many tents are in that row or column.

This is an example of a starting Tents puzzle. We can immediately see that we have a column that contains no tents, so we will insert a 'X' in each cell in that column.

We know that each tree must be paired in a 1-1 relationship with a tent. We have two trees in the column on the far-left, these two trees only have one available adjacent squares, i.e. cells A and B must contain tents.

Whenever we insert a tent anywhere, we know all surrounding cells (including diagonally) will be empty (from rule 2), so we can mark all surrounding cells as empty.

After inserting a tent in cell B, this row can't contain any more tents, so we will insert a 'X' in each cell in this row as well.

A few observations we can make here,

1. Cells A and B must empty - there are no trees adjacent to these two cells, so they must be empty.
2. The bottom row needs 3 tents in total, having taken out two cells we are left with exactly 3 remaining cells, so these must contain tents.
3. We know the column on the left contains 4 tents in total, we have two already. This means cells C, D and E contains 2 tents between them. The only way we can do this is to insert tents in cells C and E.

We now have the top row and a column on the right of the puzzle are complete, so we can mark these as empty.

We know that the column on the right side of the grid contains one tent, the only cell this could be is the cell marked 'A'. This completes this column, so we will mark all remaining cells in that column as empty.

We also know that the tree above cell B must be adjacent to a tent. The only option is cell B, so we will insert a tent in cell B. This completes this column, so we will mark all remaining cells in that column as empty.

We will also mark all surrounding cells as empty.

We know the column containing cells A and B must contain 2 tents, the only cells available are cells A and B, so we will insert a tent in both these cells.

We know the row containing cell C must contain 2 tents - we have one already, cell C is the only remaining option, so we will insert a tent in cell C.

Similarly for cell D - this row must contain 2 tents, we have one already, cell D is the only remaining option.

Following the clues, we know that cells A, B and C must contain tents - they are the only available cells left to satisfy the clues.

Our completed Tents puzzle!