The man in the blue shirt is working on the light.
A man working on a light.
A man in a blue shirt working on a light and a man working on a light are basically interchangeable and mean the same thing.
exists e1 s1 x1 x2 x3.(n_light(x3) & n_shirt(x2) & a_blue(s1) & Theme(s1,x2) & n_man(x1) & on(e1,x3) & Actor(e1,x1) & v_work(e1) & in(x1,x2))
exists e1 x1 x2 x3.(a_topic(x1) & on(e1,x3) & n_light(x3) & Actor(e1,x2) & v_work(e1) & (x1 = x2) & n_man(x1))