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

Distractor grid 1:

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 ▢ ▢

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 has a single row of X's at the top and bottom, and a single column of X's on the left and right sides. The remaining cells are empty.
assistant
Expression: The target grid has a 5x5 grid with a filled X pattern on the top and bottom rows, and a single filled X cell in the middle of the second row.
assistant