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
X X X X X

Distractor grid 1:

X X X X X
▢ ▢ ▢ ▢ ▢
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 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: A completely filled 5x5 grid with all cells marked as "X".<|end|>
assistant
Expression: The grid with a continuous block of X's in the top-left corner, followed by a row of empty cells, and then another continuous block of X's filling the remaining cells.

This expression distinguishes the target grid from the distractors by highlighting the unique pattern of continuous blocks of X's and empty cells (▢) in the target grid. The distractors have different patterns, with the first having a continuous block of X's in the
assistant