setting up multiple dhcp pools on on eth int

[pctechnician]

I want to set up two dhcp pools on FA 0/0 on the 2620 routers. I understand that you have to set them up on sub interfaces , but im not familiar with the concep of the ip dhcp relay.

I cant type: router(config-subif)# ip dhcp pool
on the sub-int, all i can do is:

(config-subif)# ip dhcp relay

could anyone help?

A+,Network+,MCP