A man in a striped sweater writes on a small rectangular chalkboard.
A man is writing on a small chalkboard.
The small chalk board the man is writing on has to be the same one so it has to be rectangular.
exists e1 s1 s2 s3 x1 x2 x3.(on(e1,x3) & n_chalkboard(x3) & a_rectangular(s3) & Theme(s3,x3) & a_small(s2) & Theme(s2,x3) & Actor(e1,x1) & v_write(e1) & in(x1,x2) & n_sweater(x2) & a_striped(s1) & Theme(s1,x2) & n_man(x1))
exists e1 s1 x1 x2.(on(e1,x2) & n_chalkboard(x2) & a_small(s1) & Theme(s1,x2) & Actor(e1,x1) & v_write(e1) & n_man(x1))