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 ▢

Distractor grid 1:

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

Distractor grid 2:

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: In the target grid, there are five rows and five columns, with a grid layout consisting of empty cells marked with "▢" and filled cells marked with "X". The top row has two "X"s and two empty cells, while the second row has three "X"s and two empty cells. The third row has three empty cells and two "X"s, and the fourth row has five empty cells. The fifth row has three "X"s and
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Expression: Top-left 3x3 region contains X's
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