A traveling boy looks sad.
A child is depressed about having to visit his grandma.
He may sad for some other reason than  about having to visit his grandma.
exists e2 e1 p1 x1.(exists s1.(Theme(s1,x1) & a_sad(s1)) & Topic(e2,p1) & Actor(e2,x1) & v_look(e2) & n_boy(x1) & Actor(e1,x1) & v_travel(e1))
exists e1 e2 p1 x1 x2.(about(e1,e2) & Topic(e2,p1) & Actor(e2,x1) & v_have(e2) & exists e3.(Theme(e3,x2) & Actor(e3,x1) & v_visit(e3)) & n_grandma(x2) & of(x2,x1) & n_male(x1) & Theme(e1,x1) & v_depress(e1) & n_child(x1))