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

Distractor grid 1:

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 border of filled cells (X) on all four sides, with the top and bottom rows completely filled with Xs, and the left and right columns also completely filled with Xs. The second and fourth rows have three empty cells (▢) in the middle, while the third row has two empty cells (▢) at the end.
assistant
Expression: The grid with a solid border and three rows with alternating filled and empty cells in the middle.
assistant