b/f brought forward~~c/f carried forwardb/d brought down c/d carried down开T a/c的时候用到.b/f, b/d表示期初数;关帐的时候用c/f,c/d~表示期末数
c/f carry forward=b/f bring forward 期末的余额=下个月的期初c/d carry back=b/d bring back 期初的余额=上个月的期末