Have you considered something like this?
<%= form_for(@post) do |f| %>
<%= f.error_messages %>
<% [:en, :es, :fr].each do |lang| %>
<h2><%= lang %> translation</h2>
<% f.globalize_fields_for lang do |g| %>
<% [:title, :teaser, :body].each do |field| %>
<p><%= g.text_field field %></p>
<% end %>
<% end %>
<hr/>
<% end %>
<% end %>
You should be able to get those lists of regions and fields automatically. Then you only need a map of region to language name, like { en: 'English', es: 'Spanish', fr: 'French'}
and you can output the proper language name instead of the region code. (This might already be available somewhere as well.)