The Mongolian Comitative Case: The Other Way to Say "with"

Two endings for one English word

An English speaker learning Mongolian meets the word with twice and has to learn that it was never one word to begin with. Cutting bread with a knife and walking with a friend have nothing in common except the spelling. One is a tool. The other is company. Mongolian marks them with two different endings and never confuses them.

The ending for company is the comitative, and it is the ending you will use in your first real conversation, because it is how you say who you are travelling with, who you came to see, and what you want in your tea.

• Чи хэнтэй хөдөө явсан бэ?
• you who-COM countryside go-PAST Q
• "Who did you go to the countryside with?"

Nothing in that sentence corresponds to with. The three letters on the end of хэн (who) carry the whole idea, and the question word sits in the middle of the sentence where English puts it at the end.

Three forms, and the gap where a fourth should be

Most endings in Mongolian come in four spellings, one for each of the four stem vowels а, о, э and ө. The comitative is the famous exception: it has three.

Look at the last line of the table. A stem whose vowels are ө ought, by the pattern you have learned everywhere else, to take a form with ө in it. There is no such form. Өрөө (room) gives өрөөтэй, and the method writes it that way; the spelling өрөөтөй does not exist. The same goes for ү: үүл (cloud) gives үүлтэй, хүүхэд (child) gives хүүхэдтэй, хүн (person) gives хүнтэй. The front vowels share one form between the three of them.

This is not a quirk you can safely forget. It is one of the five places in the language where vowel harmony does not deliver what it promises, and it is listed with the others on The Suffixes That Do Not Follow Vowel Harmony. What you need in practice is a smaller fact: when in doubt between a front-vowel form and nothing, write –тэй. There is no fourth box to fill.

One more thing the table hides. И is a neutral vowel, so it never decides anything; the rest of the word does. Салхи (wind) has an а, so it gives салхитай. Зориг (courage) has an о, so it gives зоригтой. And when there is nothing else in the word to decide — бичиг (writing, document) has only и — the front form appears: толь бичигтэй (with a dictionary).

The most regular ending in the language

Here is a piece of good news that almost nobody tells beginners. The comitative begins with a consonant, т, and that one fact exempts it from every joining trick you have had to learn for the other cases.

No linking consonant, no vowel lost: the ending simply lands on the word exactly as the word is spelled. Set the two endings side by side and the difference is visible at a glance.

In the middle column the stem itself has been altered to make room for the ending. In the right-hand column it has not been touched: бэлэг keeps its э, малчин keeps its н, сүү gains nothing but the three letters. So once you have settled the vowel class, you are done. What is happening in the middle column — and for which cases — is on How a Mongolian Word Is Built: Stem Plus Suffixes; you can read that page knowing that none of it applies here.

Who came along

The core meaning is accompaniment, and it works for people and for things alike.

• Тэр нэг малчинтай өчигдөр уулзсан. (He met a herder yesterday.)
• Би их бэлэгтэй ирсэн. (I arrived with a lot of gifts.)
• Бид махтай будаа идмээр байна. (We want to eat rice with meat.)
• Та сүүгүй кофе уумаар байна. (You want coffee without milk.)

Two of those sentences are worth a second look. In the third, махтай stands in front of будаа (rice) and modifies it: "meat-with rice". English would say "rice with meat" and put the extra thing last. Mongolian puts whatever describes a noun in front of the noun, without exception, which is why the order looks reversed. That ordering rule is the subject of Mongolian Word Order.

And in Энэ суудал хүнтэй юү? (Is this seat taken?) the ending does something English cannot imitate at all. Word for word it asks "is this seat with-a-person?". There is no verb, no passive, no "taken" — just a noun with the comitative on it, and the question particle. A learner who waits to find a verb will wait a long time.

хамт, and the verbs that insist on the ending

Хамт (together) is a separate word, not an ending, and it often sits after a noun that already carries the comitative. It adds the sense of doing something jointly rather than merely being accompanied:

• Бат надтай хамт ажилладаг. (Bat works with me.)
• Та бидэнтэй хамт явах уу? (Will you come with us?)
• Тэдэнтэй хамт тоглоё. (Let's play with them.)

Then there is a group of verbs that take the comitative where English takes a plain object, and these are the ones that catch learners out. English "I met him" has a direct object; Mongolian says "I met with him" and will not accept anything else:

• Би чамтай өчигдөр уулзсан. (I met you yesterday.)
• Би тантай утсаар ярьсан. (I spoke with you on the telephone.)

That second sentence is the cleanest demonstration of the two-ending split on the whole page. Тантай is the person, so the comitative. Утсаар is the telephone, so the instrumental. English says "with you on the phone" and the preposition changes for reasons of idiom; Mongolian changes the ending for a reason of meaning. Which of the two "with" endings to choose, case by case, is set out on The Mongolian Instrumental.

Beware of one more look-alike. Buying or asking something of a person is not accompaniment but origin, and Mongolian treats it as such: you buy дэлгүүрээс (from the shop), not with it. That ending has its own page, The Mongolian Ablative.

Turning the ending over: –гүй for "without"

The opposite of this case is not formed by adding a negative word in front. It is formed by replacing the ending. Where –тай, –той, –тэй says "having", –гүй says "lacking", and the two swap places on the same stem:

Read the right-hand column again and notice what is not happening. –Гүй never changes. Not after а, not after о, not after ү. There is no –гуй and no –гой. So the positive ending bends to the word and the negative one does not, which is what makes the pair sit so oddly side by side. Its status in the harmony system is argued on The Suffixes That Do Not Follow Vowel Harmony, and its place in the wider machinery of saying no — alongside үгүй, биш, байхгүй and битгий — is on Saying No in Mongolian.

Two more pairs are worth having by heart because they turn up constantly and do not look like cases at all: дуртай (fond of) against дургүй (not fond of), and хэрэгтэй (needed) against хэрэггүй (not needed). They are built on exactly this ending; what they mean and what they do to the rest of the sentence belongs to Can, Must, Want, Like.

What else this ending does, and where to read about it

Two further uses are genuinely this ending's work but are housed elsewhere, because each of them is a whole problem in itself.

The first is possession: Mongolian has no verb for to have and this ending is one of the three ways round that gap, which is how Би таван морьтой comes to mean that the speaker owns five horses — the gap, and all three ways of filling it, are on байна: "To Be", "There Is", and Having No Verb for "To Have".

The second is word building: the same three letters also turn a noun into an adjective, which is where азтай (lucky), амттай (tasty) and үүлтэй (cloudy) come from, and that family of suffixes is on Building New Words. The useful thing to know here is that you never have to decide which of the two you are looking at, because the choice between –тай, –той and –тэй is made the same way either way.

What stacks on top of it

The comitative is not always the last thing on the word: a further ending can follow it, which is what gives –тайгаа and –тэйгээ in найз нартайгаа, эцэг эхтэйгээ and Та толь бичигтэйгээ ирсэн үү? (Did you come with your dictionary?) — what that extra piece does, and why English has nothing to match it, is on The Reflexive Possessive. Worth noticing in passing: эцэг эхтэйгээ (with one's own parents) is two words carrying one set of endings, and they go on the second word only.

An older comitative, surviving in a handful of words

You will meet a small set of words that look like comitatives of numbers but do not follow the rule above: хоёулаа, дөрөвүүлээ, хэдүүлээ. The method identifies them as the remains of an older comitative in –луугаа and says plainly that the process is no longer in use and survives in a few words; different sections of the book even spell them differently, with хэдлүүгээ beside хэдүүлээ.

• Та нар хэдүүлээ вэ? (How many of you are there?)
• Бид дөрөвүүлээ. (There are four of us.)
• Хоёулаа цуг тоглоё. (Let's play, the two of us.)

That is the comitative. Three forms, no form in ө, nothing to adjust at the seam, one invariable negative counterpart, and a meaning that covers everything English does with with except the one thing it hands to the instrumental.