Relative clauses are translated into English as phrases beginning with who, which, where, and, most commonly, that. Like adjectives, they describe nouns: the dog which is running, the cat that is sleeping, the child who is playing, the restaurant where we ate. The noun modified by a relative clause is the head noun.

In Klingon, the verb in the relative clause ends with the Type 9 suffix -bogh, which will, for convenience, be translated which.

Whether the head noun follows or precedes the relative clause depends on its relationship to that clause. Compare the following:

qIppu'bogh yaS officer who hit him/her

yaS qIppu'bogh officer whom he/she hit

In both phrases, the relative clause is qIppu'bogh (qIp hit, -pu' perfective, -bogh which), and the head noun is yaS officer. In the first phrase, yaS is the subject of the verb qIp (the officer is doing the hitting), so it follows qIppu'bogh, just as all subjects follow the verb. In the second phrase, yaS is the object (the officer is getting hit), so it precedes qIppu'bogh, just as all objects precede the verb.

The whole construction (relative clause plus head noun), as a unit, is used in a sentence as a noun. Accordingly, this construction follows or precedes the verb of the sentence, depending on whether it is the subject or object.

qIppu'bogh yaS vIlegh I see the officer who hit him/her.

The entire relative construction qIppu'bogh yaS officer who hit him/her is the object of the verb vIlegh I see him/her, so it precedes the verb.

mulegh qIppu'bogh yaS The officer who hit him/her sees me.

Here, qIppu'bogh yaS is the subject of the verb mulegh he/she sees me, so it follows the verb.

This pattern is also followed when the head noun is the object of the verb in the relative clause, such as yaS qIppu'bogh officer whom he/she hit.

yaS qIppu'bogh vIlegh I see the officer whom he/she hit.

mulegh yaS qIppu'bogh The officer whom he/she hit sees me.

In the English translation, the relative pronouns (that, which, etc.) may often be omitted: I see the officer he/she hit, the officer he/she hit sees me. In Klingon, however, -bogh is mandatory.


This suffix creates a relative clause. In English, a relative clause usually has a relative pronoun (see the list in the translation section below). The relative clause modifies a noun.

Consider the sentence:

  • qet loD - A man runs.

The relative clause is based on this sentence. The phrase "the man who is running" is comprised of a relative clause and a head noun. The relative clause is "who is running" and the head noun is "a man".

In Klingon, the relative clause is formed by adding "-bogh" to the verb to give "qetbogh".

So we have:

  • qetbogh loD - a man who is running

This phrase, relative clause and head noun, together function in a sentence as a noun. This noun can occur as either subject or object.

So, as subject:

  • HoH qetbogh loD - A man who is running kills.

Or as object:

  • qetbogh loD HoH - He/she kills a man who is running.

In English, we can also phrase this sentence using a present participle. The present participle functions as an adjective, and there is no relative clause or relative pronoun.

In this example the participle would be "running":

  • qetbogh loD HoH - He/she kills a running man.

If the relative clause itself contains a noun, then the head noun is indicated by -'e':

  • loD HIvbogh be"e' - the woman who attacks the man
  • loD'e' HIvbogh be' - the man who is attacked by the woman

A relative clause can also be used to translate constructions such as "a man in a coat". This can be rendered:

  • wep tuQbogh loD'e' a man who is wearing a coat

Additional Information on -bogh from outside TKD:

LS: We know that the head-noun of a relative clause can be the subject or the object; the question is, can it be any other case? Nick Nicholas has pointed out that Terrestrial languages follow an accessibility hierarchy for the heads of relative clauses, first subjects, then direct objects, followed in by order indirect objects, possessors,  and comparatives. Now, no one said that Klingon has to follow the Terran hierarchy

MO: In fact it shouldn't! I don't think Klingon fits into this hierarchy. Well, it does, if you want to look at it that way. I couldn't make the {-bogh} thing work for me with anything other than subject or object.

LS: It fits in the hierarchy way at the bottom.

MO: Yeah, it's klutzy.

LS: So only the subject or object of a verb can be the head-noun of a relative clause. It doesn't allow possessing nouns either?

MO: Right.

LS: Then how can we say "The ship on which the captain kills the prisoners is very large?"

MO: I would do it with two sentences.

LS: Just say "The ship's big," and "the captain kills prisoners on it."

MO: Yeah. You can probably do all kinds of topicalizing things about the ship, if you're talking about the ship and want to make a big deal about the fact that it's big.

LS: tInqu' Duj'e'

MO: Yeah... "As far as the ship is concerned, it's big, and the captain kills a prisoner on it too."

LS: That's another thing people have been hassling about, because you called "'e'" the topic marker, and all the time you use it as a focus marker.

MO: And they're making the distinction... You're using topic like topic/ comment.

LS: You've been saying things like "As for the ship, it's big, which is focus."

MO: I stand corrected.

LS: So it really is a focus marker, then?

MO: Yeah.

LS: If you have a noun in one case in the relative clause and use it in another in the main clause... I guess you'd have to use the two-    sentence trick.

MO: Yes. What I find myself doing a lot, especially with these Skybox things... The English is these long, long complicated sentences, and I said, "no way," I'd take this long sentence and split it up into two or three. So they went and counted the periods, and said "wait a minute, we gave you two sentences, you're giving us back six, what's going on here?"

LS: Back to relative clauses...

MO: One of the things you talk about was ambiguity. DujDaq puq DaqIppu'bogh vIlegh I see the child who you hit on the ship, or on the ship I see the child... and that's ambiguous. . I thought about it and I said "That's fine." And it's ambiguous in exactly the same way that English is. You want ambiguity in language, I would think. It's not math. I was reading this bit about "I see the child you hit on the ship," and for whatever reason what popped into my head was Groucho Marx, that old Groucho Marx joke, you know, "I just shot an elephant in my pajamas... and how he got in my pajamas I'll never know." You can say that in Klingon, no problem; they'll get the joke. There's not many jokes you can get to translate into Klingon, but that one would work.

LS: Somebody was asking about if you have two nouns that both have {-'e'} on them, and they're conjoined with {je}, do you put the {-'e'} on the {je} or on the nouns?

MO: Right. Can you topicalize a conjunction? I don't know... nah... Though actually for me, one of the things that pleases me about all this stuff is not so much when people talk about the details of the language, although that's fine, is when they talk about language at all. So this guy came up with this idea of putting {-'e'} at the end, that's a very clever idea, right or wrong.

LS: People are constantly saying "how would I say 'I killed the Ferengi with the phaser,' there's no word for 'this'," there's no instrumental, So people have been doing things like " In order to kill the Ferengi, I used the phaser."

MO: Good. Good for them. That's exactly right.