A motorcyclist on the street.
A human is sleeping.
Calling someone a motorcyclist implies that they are riding the motorcycle at the time, which they cannot do while sleeping.
exists x1 x2.(n_street(x2) & a_topic(x1) & on(x1,x2) & n_motorcyclist(x1))
exists e1 x1.(Actor(e1,x1) & v_sleep(e1) & n_human(x1))