Theory "chess".

There is 1 board.
There are 64 squares.
There are 2 colors: white, black.
There are 2 shades: light, dark.
There are 32 pieces.

A piece has a color.
A square has a shade.
There are 8 columns: a, b, c, d, e, f, g, h.
There are 8 rows: 1, 2, 3, 4, 5, 6, 7, 8.
A square has a column and a row.

The board has all squares.

One piece is called "white king".
Another piece is called "black king".
Another piece is called "white queen".
Another piece is called "black queen".
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A piece can "be on" a square.
Only one piece can "be on" a square.

A piece with a color of white is called "white piece".
A piece with a color of black is called "black piece".
A square with a shade of light is called "light square".
A square with a shade of dark is called "dark square".