General :: Add A User Using The Useradd Command?

I am trying to learn shell scripting from a book and all I am doing is following few instruction from the book. Now this is what I am doing. I am trying to add a user using the useradd command so I run the following at command prompt root@S8500C_9>useradd ajit. The first time when I add this user I was successful.Later I deleted this suer using the userdel -r ajit command.Now when again I am trying to add this user it gives me following error. useradd: group ajit exists - if you want to add this user to that group, use -g. Now when I try using the -g option with the useradd command it gives we all the set off options avaiable to use along with the useradd command but doesnt create the ajit use