As I recall they read poetry when courting their Lady Love, while she throws furniture at them.
Vorpal?
Won’t you borrow a word to describe something you language doesn’t have…like Europeans did for a animals when the traveled to the New World?
Heavy objects. Furniture is acceptable but not necessary. And there’s more, like the bit about going into the woods and killing something and bringing its carcass back so you can cook it and feed it to your ladylove.
Wimps.
What? I didn’t say they don’t throw chairs. I just meant that if the guy is quoting the love poetry in a the middle of the woods, the girl doesn’t have to wait until she’s inside to respond, but rather can pick up any availabel bough, raccoon, or battle-ax.
When bringing a concept across to a new language, you have options. You don’t always want to just adapt a foreign word to the target language. It can throw up a barrier to communication, because suddenly the audience is confronted with a word they can’t digest immediately. Sometimes it’s worth constructing a circumlocution to get around the lack of the exact word in the target language.
But, um, yeah. If you’re talking about carrying a made-up word into a made-up language, what’s the problem? Well, I’d say for one thing that these invented words work because they sound like the parts of speech they represent, which is then re-enforced with word order. ‘Vorpal’ ends in ‘-al’ which makes it ring adjectival to English ears. What would it take in Klingon? Also, what contextual arrangements would you need to re-enforce it?
My understanding was that Klingon was purposely designed to be difficult to learn and speak. It’s a sort of meta-linguistic double dog dare.
Speaking of which, I wonder how you’d translate that. Is it a dare two dogs in proportion, or is a double dare that is dog-like? Or does ‘dog’ intensify ‘double’?
This reminds me of a Dilbert cartoon.
Dogbert walks in and sees Dilbert sitting there and asks him what he is doing.
Dilbert responds that he just bought the first video phone.
Dogbert asks what he’ll do now and Dilbert responds that he is waiting for someone else to buy one.
Dogbert opines that the scary part is technology couldn’t move forward if not for people like Dilbert. 
Having parodied Jabberwocky for the thread “If A Chritmas Carol Were Written by Someone Else,” I can tell you (to paraphase Issac Asimov when he tried to write like Ogden Nash) it’s only easy if your name is Leiws Carroll.
Yeah…by each other. The rest of us call them trekkies. It’s a diminutive, nonrespect thing.
Come, Sir, that is Bold Talk, given your user name. 
nerd fight!
Fight! Fight! Fight! Fight! Fi- oh, shit, run guys, here comes the teacher!
He was the first to become conversant, in that he could talk without constantly referring to a dictionary. But there were others with various other degrees of skill. So he had other people to talk to, he just had to pause a lot for them to decipher what he’d said or compose their replies.
When I hung out with him and his girlfriend (also a conversant Klingon speaker), the three of us spoke Klingon to each other. I’ve conversed in Klingon with other people as well.
I would estimate that there are about 30 people who are conversant in Klingon, in being able to hold a conversation without pausing to consult a dictionary. Also, not all Klingon speakers are Star Trek fans. Some of them are in it for the linguistics.
Zombies speak Klingon?
Yes, they do, but with poorly enunciated sibilants.
The shredded lips and missing teeth are always a problem.
**And, it is Trekker not trekkie. ** Do not be dismissive of a cultural phenomenon that has lasted for well nigh 50 years. It has had widespread impact upon the American technological landscape and upon the men and women who grew up looking to the stars.
<waves cane in air and shouts something unintelligible at those kids on his lawn>
There’s gotta be a way to say THAT in Klingon!
The closest I can get is: SoH puqpu’ pol lItha’ vo’ wIj [lawn]
Apparently, the word ‘lawn’ doesn’t exist in the lexicon… yet.
It would probably be a death threat.
“Foul my grass no more, lest ye wish to be fed your own intestines.”
I have been to any number of SF conventions over the last 25 years, and to hear Trekkers decked out in Klingon makeup and garb discussing in Klingon where they plan to have lunch or what panel they have next is not unusual. There are Star Trek associations where the members meet regularly, and these produce smaller groups of people who practice their Klingon with each other on a weekly, if not daily, basis. So, yes, there are people conversant in Klingon.