I am using a free account and would like to use my 10th and last user be set up so that 3 different email addresses direct mail to the same inbox. Is that possible? 

For example, I'd like 1@zh.com, 2@zh.com, and 3@zh.com all point to 4@zh.com. 1, 2, 3 doesn't really need full functionality of a user mailbox (doesn't need to send or any of the apps) but 4 does and would handle correspondence for 1,2 and 3. 

Is that possible? Or would 1, 2 and 3 all need to be separate users? 

Thanks!