Or you can just use a list:

for i in serverA serverB serverC serverD serverE; do
  ssh -1 $i "echo `pwd`"
done

I was going to suggest what Scrutinizer suggested, but he beat me too it.

Are you using keychain? It's available in the repositories of most Linux distros.

With it, I am prompted for my passphrase the first time I login after a reboot of my local machine. It keeps a process running, even if I logout, that maintains the passphrase in memory. Then when I use ssh or scp (even via cron when logged out) the keychain process supplies the passphrase. It's as safe as your local login.

Either loops work, the problem is ssh-ing to the servers itself. I can ssh serverB on the command line without being prompted for a password. However when i use the script to do it, i'm being prompted for a password and i don't know the password to access these servers. Do you think i should add the known host on remote server ? I'm not using keychain -- I don't even know the passpharase of the existing keys. What should i do?

If you don't know either the password or the SSH passphrase for any username on the servers, one wonders if you should be attempting this. If you are doing something that you are supposed to be doing, then you should reasonably demand the access you need to do it.

The way to get SSH to work without a password is to append your public key from the local machine to the ~/.ssh/authorized_keys file on the remote machine. When the known_hosts file give me trouble, I delete it and it starts over.