 "Thick" notebooks must be either ruled with 6 mm, 7 mm, 8 mm, 9 mm spacing between the lines, or graph-ruled with 3 mm, 4 mm, 5 mm, 6 mm, or 7 mm squares.The paper for cursive writing uses pairs of lines 4 mm apart, with 8 mm between the pairs.They may also have angled lines at 65 degrees to vertical to provide additional guidance.