Hollow brick with foot portions

A hollow brick configured to be assembled with a plastic corrugated plate, the hollow brick comprising:

• a bottom wall having two opposite longitudinal sides and two opposite transverse sides connected between said longitudinal sides;
• two side walls projecting respectively and upwardly from the two opposite transverse sides of said bottom wall;
• a plurality of intermediate walls projecting upwardly from said bottom wall between said side walls and spaced apart along a direction parallel with said longitudinal sides of said bottom wall;
• a top wall opposite to said bottom wall and connecting said side walls and said intermediate walls;
• a plurality of ventilation holes bounded by said bottom wall, said side walls, said intermediate walls and said top wall, each of said ventilation holes having two ventilation open ends opposite to each other along a line parallel with said transverse sides of said bottom wall;
• said bottom wall having a plurality of foot portions projecting downwardly and spaced apart from each other, and a plurality of bottom grooves, each of said bottom grooves located between two adjacent ones of said foot portions;
• wherein a central axial line of each of said foot portions is collinearly aligned with a central axial line of one of said side walls and said intermediate walls;
• wherein said hollow brick further includes two outer holding ribs projecting respectively from outer surfaces of said side walls in opposite outward directions;
• and
• wherein each of said outer holding ribs has a top flat surface facing upwardly configured to support a respective part of the corrugated plate, each said top flat surface and one of said outer surfaces of said side walls defining a limiting corner having an angle of not larger than 90 degrees.