The man in the blue hat riding the bike is in the lead.
Race car drivers speed by.
The man in the blue hat riding the bike is in the lead.  There are no race car drivers speeding by.  The man is riding a bike.
exists e1 p1 s1 x1 x2 x3 x4 x5.(n_lead(x5) & n_bike(x4) & n_hat(x2) & a_blue(s1) & Theme(s1,x2) & n_man(x1) & in(x1,x5) & in(x1,x2) & Theme(e1,x4) & Actor(e1,x3) & v_ride(e1) & (x2 = x3))
exists e1 s1 x1 x2 x3.(a_by(s1) & Manner(e1,s1) & Actor(e1,x1) & v_speed(e1) & n_driver(x1) & of(x1,x3) & n_car(x3) & (x1 = x2) & ne_nam_race(x2))