A man in a gray shirt playing a whistle.
Just a dog.
Just a Dog contradicts with A man in first sentence.
exists e1 s1 x1 x2 x3 x4.(a_topic(x1) & in(x1,x2) & Theme(e1,x4) & Actor(e1,x3) & v_play(e1) & n_whistle(x4) & (x2 = x3) & n_shirt(x2) & a_gray(s1) & Theme(s1,x2) & n_man(x1))
exists x1.(a_topic(x1) & r_just(x1) & n_dog(x1))