A bicyclist falls off his bike while others watch.
The people didn't notice the man fall.
The others can not watch when they didn't notice the man.
exists e1 p1 s1 x1 x2.(exists e2 x3.(Actor(e2,x3) & v_watch(e2) & -(x3 = x1) & n_person(x3)) & n_person(x1) & while(e1,p1) & a_off(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_fall(e1) & n_bike(x2) & of(x2,x1) & n_male(x1) & n_bicyclist(x1))
exists x1 x2 x3.(n_fall(x2) & of(x2,x3) & n_man(x3) & n_people(x1) & -exists e1.(Theme(e1,x2) & Actor(e1,x1) & v_notice(e1)))