Man in brown shirt accepting a certificate.
A man in black shoes is getting a certificate.
A man in a brown shirt is not necessarily wearing black shoes. Men can wear different colored shoes.
exists e1 s1 x1 x2 x3 x4.(a_topic(x1) & in(x1,x2) & Theme(e1,x4) & Actor(e1,x3) & v_accept(e1) & n_certificate(x4) & (x2 = x3) & n_shirt(x2) & a_brown(s1) & Theme(s1,x2) & n_man(x1))
exists e1 s1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_get(e1) & n_certificate(x3) & in(x1,x2) & n_shoe(x2) & a_black(s1) & Theme(s1,x2) & n_man(x1))