app/views/illnesses/edit.html.erb
<h1>Edit illness</h1>
<%= form_for (@illness) do |f| %>
<%= f.label :name %><br/>
<%= f.text_field :name %><br/><br/>
<%= f.label :description %><br/>
<%= f.text_area :description %><br/><br/>
<%= f.label :priority %><br/>
<%= f.select :priority, [:low, :medium, :high] %><br/><br/>
<%= f.label :treatment %><br/>
<%= f.text_area :treatment %><br/><br/>
<%= f.submit %>
<% end %>