A young man lifting the lid to a dumpster.
A little boy opening a dumpster to put trash in it.
Young man could mean a male older than a little boy.  Just because he is lifting the lid on a dumpster does not imply he is doing it to put trash in it.  He could be lifting the lid for another reason.
exists e1 s1 x1 x2 x3 x4.(n_lid(x3) & a_topic(x1) & to(e1,x4) & n_dumpster(x4) & Theme(e1,x3) & Actor(e1,x2) & v_lift(e1) & (x1 = x2) & n_man(x1) & a_young(s1) & Theme(s1,x1))
exists e1 p1 s1 x1 x2 x3 x4.(a_topic(x1) & Topic(e1,p1) & exists e2 x5.(in(e2,x1) & Theme(e2,x5) & Actor(e2,x2) & v_put(e2) & n_trash(x5)) & n_thing(x1) & Theme(e1,x4) & Actor(e1,x3) & v_open(e1) & n_dumpster(x4) & (x1 = x3) & (x1 = x2) & n_boy(x1) & a_little(s1) & Theme(s1,x1))