How to have a bunch of recommended packages?

Can I have a set of recommended packages in my package?

Let's say I am building package1. This recommends package2, package3 and package4, but all of them need to be installed in order to provide a specific functionality!

For example, it would be no use for the user to install only the recommended packages package2 and package3 without the package4.

How can I tell it at debian/control that these recommended packages have immediate relation between them and cannot be installed separately?:confused:

See http://www.debian.org/doc/debian-policy/ch-relationships.html#s-binarydeps for how to do it.

Thanks, I will have a look t̶o̶m̶o̶r̶r̶o̶w̶ later today (it is 2:17 here :P)