Error returned after rebooting after modifying iptables

This is how I changed vi / etc/sysconfig/iptables after adding rules to the firewall.

-An INPUT-m state-- state NEW-m tcp-p tcp-- dport 21-j ACCEPT

Restart: / etc/init.d/iptables restart

Return value: Error occurred at line: 16

Try `iptables-restore-h' or 'iptables-restore-- help' for more information.

[FAILED]

Find a solution:

/ sbin/iptables-I INPUT-p tcp-- dport 21-j ACCEPT

/ etc/rc.d/init.d/iptables save

/ etc/init.d/iptables restart

Restart successfully: iptables: Setting chains to policy ACCEPT: filter [OK]

Iptables: Flushing firewall rules: [OK]

Iptables: Unloading modules: [OK]

Iptables: Applying firewall rules: [OK]

# the command to block a single IP is

Iptables-I INPUT-s 123.45.6.7-j DROP

# the command for the whole paragraph from 123.0.0.1 to 123.255.255.254

Iptables-I INPUT-s 123.0.0.0 iptables 8-j DROP

# IP paragraphs are commands from 123.45.0.1 to 123.45.255.254

Iptables-I INPUT-s 124.45.0.0 DROP 16-j

# commands for IP paragraphs from 123.45.6.1 to 123.45.6.254 are

Iptables-I INPUT-s 123.45.6.0 Universe 24-j DROP