A crowd is outside watching someone in the center of them.
A crowd has surrounded someone they are not watching.
you can either be watching or not watching something
exists e1 s1 x1 x2 x3.(n_center(x3) & a_outside(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_watch(e1) & in(x2,x3) & of(x3,x1) & n_thing(x1) & n_person(x2) & n_crowd(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_surround(e1) & -exists e2 x3.(Theme(e2,x3) & Actor(e2,x1) & v_watch(e2) & (x2 = x3)) & n_thing(x1) & n_person(x2) & n_crowd(x1))