A large group of people have formed a line outside.
A group of people line up outside.
'To form a line' can be rephrased as 'to line up.'
exists e1 s1 s2 x1 x2 x3.(a_outside(s2) & Manner(e1,s2) & Theme(e1,x3) & Actor(e1,x1) & v_form(e1) & n_line(x3) & of(x1,x2) & n_people(x2) & n_group(x1) & a_large(s1) & Theme(s1,x1))
exists e1 x1 x2 x3.(up(e1,x3) & n_outside(x3) & Actor(e1,x1) & v_line(e1) & of(x1,x2) & n_people(x2) & n_group(x1))