A bus being worked on by a mechanic.
A bus races a truck in a drag race.
if the truck is being worked on it can not be in a drag race.
exists e1 s1 x1 x2 x3.(a_topic(x1) & Actor(e1,x3) & n_mechanic(x3) & a_on(s1) & Manner(e1,s1) & Theme(e1,x2) & v_work(e1) & (x1 = x2) & n_bus(x1))
all x1.(n_truck(x1) -> exists x2 x3 x4 x5.(a_topic(x2) & in(x2,x4) & n_race(x4) & of(x4,x5) & n_drag(x5) & for(x2,x1) & n_race(x2) & of(x2,x3) & n_bus(x3)))