A man in a gray shirt playing a whistle.
a guy in gray uses a whistle
A man in gray plays a whistle because a man and guy are a way to describe a male and the man is playing the whistle since this is one way to use it.
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.(all x2.(n_whistle(x2) -> exists s1 x3.(a_topic(x1) & in(x1,x3) & for(x3,x2) & n_use(x3) & a_gray(s1) & Theme(s1,x3))) & n_guy(x1))