question about 3rd party ads

is it possible to publish 3rd party ads in my site? is it ligal? i want to add a forum in my wordpress site, it says that creating a forum in wordpress in not ligal here.i want to clear the topic.
and is it possible to add a .tk domain?

[saitfainder]

I'm not sure I've exactly understood your question. Anyway external advertising is not admitted, as reported in our terms of service. But you can install any application you want in your web space, so you can have a blog and a forum and everything else your need.

unable to register a subdomain to m.khulnatech.altervista.org for my wordpress site .any help!

you need to know about the terms and conditions of the altervista, then i think you can add third party application in your appplication(website)