CHESSDORRABack-rank mate
How the king’s own pieces can trap it.
The checking line and escape squares
A rook or queen checks along the back rank. Look at the squares in front of the king: its own pieces may occupy them, or the opponent may control them. Then test captures and blocks.
Giving the king room
Moving a pawn in front of the king can create an escape square. Before pushing it, check whether the new square will be safe and which other squares the pawn move weakens.