There is a large crowd of runners.
The group is running a marathon.
Large crowd of runners does not necessarily mean running a marathon.
exists p1 x1 s1 x2 x3.((x1 = x2) & of(x2,x3) & n_runner(x3) & n_crowd(x2) & a_large(s1) & Theme(s1,x2))
exists e1 x1 x2.(n_group(x1) & Theme(e1,x2) & Actor(e1,x1) & v_run(e1) & n_marathon(x2))