<nav>
  <ul>
    <li><%= link_to "Home", root_path %></li>
    <% if user_signed_in? %>
      <li><%= link_to "Add Resource", new_resource_path %></li>
      <li><%= link_to "Add Language", new_language_path %></li>
      <li><%= link_to "Log out", destroy_user_session_path, method: 'delete' %></li>
    <% else %>
      <li><%= link_to "Sign in", new_user_session_path %></li>
      <li><%= link_to "Sign up", new_user_registration_path %></li>
    <% end %>
  </ul>
</nav>

<nav>
  <ul>
    <li><%= link_to "Home", root_path %></li>
    <% if user_signed_in? %>
      <li><%= link_to "Add Resource", new_resource_path %></li>
      <li><%= link_to "Add Language", new_language_path %></li>
      <li><%= link_to "Add Course", new_course_path %></li>
      <li><%= link_to "Log out", destroy_user_session_path, method: 'delete' %></li>
    <% else %>
      <li><%= link_to "Sign in", new_user_session_path %></li>
      <li><%= link_to "Sign up", new_user_registration_path %></li>
    <% end %>
  </ul>
</nav>

Add Course link to nav.
Add Course link to nav.
