The boy in the red shirt is next to a blue wall.
The boy with no shirt is flying.
it is not possible to have a red shirt and no shirt at the same time
exists s1 s2 s3 x1 x2 x3.(n_shirt(x2) & a_red(s1) & Theme(s1,x2) & n_boy(x1) & to(s2,x3) & n_wall(x3) & a_blue(s3) & Theme(s3,x3) & Theme(s2,x1) & a_next(s2) & in(x1,x2))
exists x1.(n_boy(x1) & -exists e1 x2.(Actor(e1,x1) & v_fly(e1) & with(x1,x2) & n_shirt(x2)))