In the rectangle with both diagonals and a flat line a quarter of the way down, how many quadrilaterals (four-sided figures) are there?

Rectangles: the top strip, the part below the line and the whole, 3. Trapeziums: 3 in the top strip (cut off by the diagonals) and 2 below the line using one diagonal, 5. Two more four-sided figures sit at the left and right below the line, each bounded by a side, the line and both diagonals. Total $3+5+2=10$.