A dog holding a baseball in his mouth.
A dog is trying to catch a frisbee.
A dog that is trying to catch a frisbee will not be holding a baseball in his mouth simultaneously.
exists e1 x1 x2 x3 x4.(a_topic(x1) & in(e1,x4) & n_mouth(x4) & of(x4,x1) & n_male(x1) & Theme(e1,x3) & Actor(e1,x2) & v_hold(e1) & n_baseball(x3) & (x1 = x2) & n_dog(x1))
exists e1 p1 x1.(Topic(e1,p1) & Actor(e1,x1) & v_try(e1) & exists e2 x2.(Theme(e2,x2) & Actor(e2,x1) & v_catch(e2) & n_frisbee(x2)) & n_dog(x1))