A singer and guitarist performing.
A comedian is telling fart jokes.
Comedian refers to a single person, not to a singer and a guitarist.
exists s1 x1 x2 x3.(a_topic(s1) & subset_of(x2,s1) & n_perform(x2) & of(x2,x3) & n_guitarist(x3) & subset_of(x1,s1) & n_singer(x1))
exists e1 s1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_tell(e1) & n_joke(x2) & a_fart(s1) & Theme(s1,x2) & n_comedian(x1))