You are given three grids, where each of them is 5 by 5 in size.
Grids have empty cells marked with "▢" and filled cells marked with "X".
Your task is to generate a referring expression that best describes the target grid while distinguishing it from the two other distractor grids.
The first grid is the target grid, and the following two grids are the distractors.

Target grid:

▢ X X X ▢
X ▢ X ▢ X
X X ▢ X X
X ▢ X ▢ X
▢ X X X ▢

Distractor grid 1:

X X X X ▢
X X X ▢ X
X X ▢ X X
X ▢ X X X
▢ X X X X

Distractor grid 2:

▢ X X X X
X ▢ X X X
X X ▢ X X
X X X ▢ X
X X X X ▢

Instruction: Describe the target grid.
Generate the referring expression starting with the tag "Expression: " for the given target grid. Omit any other text.
Expression: The target grid is a 5x5 grid with filled cells marked with "X" and empty cells marked with "▢". Starting from the top-left corner, the grid has the following pattern: one empty cell, followed by three filled cells, one empty cell, two filled cells, one empty cell, two filled cells, and one empty cell. Moving to the second row, it has one filled cell, followed by one empty cell, one filled cell, two
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Expression: The target grid has an X in the center, surrounded by four corners, each containing a group of two X's forming a diagonal line with the center X. The rest of the grid is evenly filled with alternating X's and empty cells along rows and columns.
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