About [[EOL:Website-activerecord.attributes.contact.contact subject id/en]]

In this case, this is a field on the "contact us" form. But...

Everything in the "Website-activerecord.attributes" subdomain is... tricky. It's a built-in Ruby on Rails convention, used for several different things. Most notably, it will be used to construct the form for whatever is being edited, so it will be used as the name for a field on a form. Secondarily, it will be used in automated error messages, such as "Contact subject is required".

I think you can *fairly* safely treat these as if they are noun phrases in the nominative case.