A man and a boy riding their bikes together.
The boy is the mans son
The boy isn't necessarily the mans son just because they are riding their bikes together.
exists e1 s1 s2 x1 x2 x3 x4.(a_topic(s1) & subset_of(x2,s1) & a_together(s2) & Manner(e1,s2) & Theme(e1,x4) & Actor(e1,x3) & v_ride(e1) & n_bike(x4) & of(x4,x1) & n_thing(x1) & (x2 = x3) & n_boy(x2) & subset_of(x1,s1) & n_man(x1))
exists p1 x1 x2 x3.(n_son(x2) & of(x2,x3) & n_man(x3) & n_boy(x1) & (x1 = x2))