The four bicyclists are riding through the desert.
They use their muscles to ride the bike
The bicyclists must use their muscles if they are riding through the desert.
exists e1 x1 x2.(n_desert(x2) & n_bicyclist(x1) & card_eq_4(x1) & through(e1,x2) & Actor(e1,x1) & v_ride(e1))
exists e1 p1 x1 x2 x3.(n_bike(x3) & n_muscle(x2) & of(x2,x1) & n_thing(x1) & n_thing(x1) & Theme(e1,p1) & Recipient(e1,x2) & Actor(e1,x1) & v_use(e1) & exists e2.(Theme(e2,x3) & Actor(e2,x1) & v_ride(e2)))