They are riding a bike and talking at the same time.
The people are riding a speed boat together.
People who are riding a bike are on solid ground and on a different vehicle that people riding a boat which is in the water and has no wheels.
exists e2 e1 s1 x1 x2 x3.(n_time(x3) & a_same(s1) & Theme(s1,x3) & n_thing(x1) & at(e2,x3) & Actor(e2,x1) & v_talk(e2) & Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_bike(x2))
exists e1 s1 x1 x2 x3.(n_people(x1) & a_together(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_boat(x2) & of(x2,x3) & n_speed(x3))