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 grid with a diagonal line of filled cells from the top-left to the bottom-right corner.
assistant
Expression: The target grid features a unique pattern of "X" and "▢" with two horizontal rows of "X" followed by a row of "X" and "▢" and ending with a full row of "X".

In this expression, we are highlighting the distinct features of the target grid that differentiate it from the distractors. The target grid has a specific arrangement of "X" and "▢" that is not present in the
assistant