The soldier is standing tall as he observes the passing people.
a soldier watching people
The soldier observes people is the same as watching people.
exists e2 e1 p1 s1 x1 x2.(n_people(x2) & Actor(e2,x2) & v_pass(e2) & n_male(x1) & n_soldier(x1) & exists e3.(Theme(e3,x2) & Actor(e3,x1) & v_observe(e3)) & as(e1,p1) & a_tall(s1) & Manner(e1,s1) & Actor(e1,x1) & v_stand(e1))
exists e1 x1 x2 x3.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_watch(e1) & n_people(x3) & (x1 = x2) & n_soldier(x1))