Two kids wearing blue are ridding horses.
The children are reading books at school
If they are riding horses, they are not reading books at school.
exists e1 e2 x1 x2 x3 x4.(Theme(e2,x4) & Actor(e2,x1) & v_rid(e2) & n_horse(x4) & Theme(e1,x3) & Actor(e1,x2) & v_wear(e1) & n_blue(x3) & (x1 = x2) & n_kid(x1) & card_eq_2(x1))
exists e1 x1 x2 x3.(n_child(x1) & at(e1,x3) & n_school(x3) & Theme(e1,x2) & Actor(e1,x1) & v_read(e1) & n_book(x2))