A motor Cross mountain bike racer is on a very bumpy ride.
the couple is having lunch in the park
A racer suggests one person, whereas a couple suggests two. Also, a person cannot be having a bumpy ride and having lunch at the same time
exists p1 x1 x2 x3 x4 x5.(exists s1 x6.(on(x1,x6) & n_ride(x6) & a_bumpy(s1) & Theme(s1,x6) & r_very(x6)) & n_racer(x1) & of(x1,x5) & n_bike(x5) & of(x1,x4) & n_mountain(x4) & (x1 = x3) & ne_nam_cross(x3) & of(x1,x2) & n_motor(x2))
exists e1 x1 x2 x3.(n_park(x3) & n_couple(x1) & in(e1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_have(e1) & n_lunch(x2))