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


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