Two children are petting a calf.
Two children are chasing a calf around the yard
The children cannot be petting  and chasing a calf at the same time.
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_pet(e1) & n_calf(x2) & n_child(x1) & card_eq_2(x1))
exists e1 x1 x2 x3.(n_yard(x3) & around(e1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_chase(e1) & n_calf(x2) & n_child(x1) & card_eq_2(x1))