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 ▢ ▢

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 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 bottom left and right corners are empty, while there is an "X" in the top middle square.
assistant
Expression: The target grid has a pattern of filled cells ('x') forming a continuous line across the middle row, with empty cells ('□') on either side, unlike the distractor grids where either the third or fifth rows contain breaks in the sequence or the filled cells are not aligned vertically in the middle row.
assistant