premise: People are coming down a movable staircase built through a tunnel, which has three of those staircases.
hypothesis: Workers are returning from inspection.
explanation_1: People coming down a staircase might not be workers returning from an inspection.
explanation_2: Just because people are going through a tunnel doesn't mean that they are workers and doesn't mean that they are inspecting anything.
explanation_3: Not all people are workers.
premise_logic: exists e2 e1 e3 s1 x1 x2 x3 x4 x5 x6.(down(e1,x2) & through(e2,x4) & Theme(e3,x6) & Actor(e3,x5) & v_have(e3) & of(x6,x2) & n_staircase(x2) & n_staircase(x2) & n_thing(x6) & card_eq_3(x6) & (x4 = x5) & n_tunnel(x4) & Theme(e2,x3) & v_build(e2) & (x2 = x3) & a_movable(s1) & Theme(s1,x2) & Actor(e1,x1) & v_come(e1) & n_people(x1))
hypothesis_logic: exists e1 x1 x2.(from(e1,x2) & n_inspection(x2) & Actor(e1,x1) & v_return(e1) & n_worker(x1))