A child in an orange shirt is running.
A child is running.
The child is running in both sentences.  One gives more information, specifically that the child is wearing an orange shirt.
exists e1 x1 x2 x3.(Actor(e1,x1) & v_run(e1) & in(x1,x2) & n_shirt(x2) & of(x2,x3) & n_orange(x3) & n_child(x1))
exists e1 x1.(Actor(e1,x1) & v_run(e1) & n_child(x1))