How to create three objects/records using one form? And how to show validation errors for them?

I want to create a form which sends email to each recipient and then create new record in free_registration_coupons table.

I need validation of email for this form.

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Model FreeRegistrationCoupon: recipient_email, token, sender_id

For now i have this:

  class FreeRegistrationCouponsController < ApplicationController
def send_invitations
emails = [params[:recipient_email_1], params[:recipient_email_2], params[:recipient_email_3]]
emails.reject!{ |e| e.eql?("") }
if emails.present?
emails.each do |e|
FreeRegistrationCoupon.create(:recipient_email => e, :sender_id => current_user.id)
#MAILER
end
redirect_to root_path, :notice => "You just send #{emails.size} invitations!"
else
redirect_to(:back)
end
end
end
class FreeRegistrationCoupon < ActiveRecord::Base
before_save :generate_token
attr_accessor :recipient_email, :sender_id
validates :recipient_email, :presence => true, :email => true
def generate_token
self.token = SecureRandom.hex
end
end

This is form which is in other controller CarsController#confirm:

  <%= form_tag :controller => 'free_registration_coupons', :action => "send_invitations" do %>
<!-- errors -->
<%= label_tag :recipient_email_1 %>
<%= text_field_tag :recipient_email_1 %>
<%= label_tag :recipient_email_2 %>
<%= text_field_tag :recipient_email_2 %>
<%= label_tag :recipient_email_3 %>
<%= text_field_tag :recipient_email_3 %>
<%= submit_tag %>
<% end %>