Man in a black shirt walking down a large set of stairs.
A man in a white shirt is walking up the stairs.
A black shirt and a white shirt are different shirts and walking up and walking down are different actions.
exists e1 s1 s2 s3 x1 x2 x3 x4 x5.(a_topic(x1) & in(x1,x2) & a_down(s3) & Manner(e1,s3) & Theme(e1,x4) & Actor(e1,x3) & v_walk(e1) & of(x4,x5) & n_stair(x5) & n_set(x4) & a_large(s2) & Theme(s2,x4) & (x2 = x3) & n_shirt(x2) & a_black(s1) & Theme(s1,x2) & n_man(x1))
exists e1 s1 s2 x1 x2 x3.(n_stair(x3) & a_up(s2) & Manner(e1,s2) & Theme(e1,x3) & Actor(e1,x1) & v_walk(e1) & in(x1,x2) & n_shirt(x2) & a_white(s1) & Theme(s1,x2) & n_man(x1))