Mate in two is lesson 2 of 2 in Checkmate patterns practice, a checkmate course suited to players rated around 700 (beginners). Now the same patterns, one move deeper. Look at checks first, then captures. A queen sacrifice is a good move if mate follows. It has 3 interactive exercises: 3 calculated lines from real positions. You play every move on a board and get feedback straight away. The lesson is free.
What this lesson explains
For a mate in two, ask what stops the pattern. Usually one black piece guards the key square. Remove it, lure it away, or block it, even if it costs you your queen.
Recap.
A king behind its own pawns fears the back rank.
A queen next to the king needs a protector.
A king boxed in by its own pieces fears a knight check.
Knight and rook mate together near the edge.
In a mate in two, remove or lure away the guard, even with a sacrifice.
What you practise
The black king has a weak back rank, but the rook on e8 guards it, and the queen guards the rook. Mate in two.
The smothered mate needs the king boxed in. Right now g8 is still free. Put something on g8 with check. Mate in two.
You know the knight and rook mate on the h-file. Here the h-pawn is in the way. Remove it with check, even if it costs the queen. Mate in two.
Worked examples
The black king has a weak back rank, but the rook on e8 guards it, and the queen guards the rook. Mate in two. Mate in two. Your queen took the rook with check, the black queen had to take back, and your rook took again with mate.
The smothered mate needs the king boxed in. Right now g8 is still free. Put something on g8 with check. Mate in two. Smothered mate. The king could not take the queen, so the rook had to, and that filled g8. Then the knight mated on f7.