Add comments to a form

Add comments to a form

Hello,

I'm trying to add comments to a form using a subform with one field named comment, but I don't want prior comments to be editable or deleteable by anyone (except the admin).  Is there a way to only display prior comments (with a datetime, user and comment field preferably) but still be able to add new ones when editing the main form?  I'm not tied to subforms if there is an easier was to do this?