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 ▢ ▢ ▢

Distractor grid 1:

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

Distractor grid 2:

▢ ▢ 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: A grid where every column has an 'X' at the second row from the top, and all other cells are empty.
assistant
Expression: The target grid has a unique pattern of alternating rows and columns filled with Xs, while the distractor grids have different patterns of filled cells. In particular, Distractor 1 is completely filled with Xs, while Distractor 2 has an empty cell in each row and column. This pattern of alternating rows and columns filled with Xs can be found in the target grid only.
assistant