how to delete some iptables items

Hi
I followed some online instruction and set iptables rules (as below)  from
iptable -L -t nat.
DNAT       tcp  --  anywhere             anywhere           tcp dpt:119 to:
192.168.1.4:119
DNAT       udp  --  anywhere             anywhere           udp dpt:446 to:
192.168.1.7:446
DNAT       tcp  --  anywhere             anywhere           tcp dpt:446 to:
192.168.1.7:446

DNAT       tcp  --  anywhere             anywhere           tcp dpt:446 to:
192.168.1.4:446

I want delete the last item. What's the command line to do this using
iptables?

thanks


Y