A man welding what looks to be a locked locker.
He is trying to protect something
Just because a man is by a locked locker doesn't necessarily mean that he is trying to protect it.
exists x1 x2.(a_topic(x1) & exists e2 e1 p1 x3.(n_thing(x3) & Theme(e2,x3) & Actor(e2,x2) & v_weld(e2) & Topic(e1,p1) & Actor(e1,x3) & v_look(e1) & exists p2 e3 x4.((x3 = x4) & n_locker(x4) & Theme(e3,x4) & v_lock(e3))) & (x1 = x2) & n_man(x1))
exists e1 p1 x1.(n_male(x1) & Topic(e1,p1) & Actor(e1,x1) & v_try(e1) & exists e2 x2.(Theme(e2,x2) & Actor(e2,x1) & v_protect(e2) & n_thing(x2)))