Proverb: Не руби́ сук, на кото́ром сиди́шь

This proverb is a near-perfect teaching machine for the relative clause. In six words it gives you a negative imperfective imperative (the everyday way to forbid something), a relative pronoun governed by a preposition, and the prepositional case doing what it does best — marking location. Better still, the grammar is welded to an image you'll never forget: a man perched on a branch, sawing through it between himself and the trunk. Parse this line cleanly and the relative clause stops being an abstract rule and becomes a picture. We'll give it whole, break it down word by word, then put it to work in real sentences.

The proverb

The shape is a one-line command with a relative clause hung off its object: "Don't cut the branch — [the one] on which you sit." The lesson is about self-sabotage: don't destroy the very thing that supports you. Quit a job in a blaze before you've lined up the next one, badmouth the client who pays you, burn the bridge you still need to cross — you're cutting the сук you're sitting on.

Word by word

Не руби́ — "don't cut" (negative imperfective imperative)

The command is не + imperfective imperative, and that combination is the default way to tell someone not to do something in Russian. The verb руби́ть ("to chop, to cut, to fell") is imperfective, and руби́ here is its imperative; with не it becomes a prohibition: "don't (go) cutting".

Why imperfective and not perfective? Because a general "don't do X" — a standing rule, a warning that holds at all times — wants the imperfective. The perfective imperative under negation (Не сруби́! "Don't [accidentally] cut it!") would be a one-off warning against a single specific act, often carrying a note of "watch out, you might do this by mistake." A proverb is a timeless principle, so the imperfective не руби́ is exactly right.

сук — "branch" (accusative direct object)

сук is the direct object of руби́ ("cut what? — the branch"), so it stands in the accusative. Because сук is an inanimate masculine noun, its accusative is identical to the nominative — no visible ending change. That's the animacy rule at work: only animate masculine nouns (and all animate plurals) borrow their accusative from the genitive; inanimates keep the bare nominative form. So сук looks unchanged, but grammatically it is firmly the accusative object here.

(A note for the curious: сук has a slightly irregular plural — сучья / су́чьев — but the singular accusative is the plain сук.)

на кото́ром сиди́шь — "on which you are sitting" (the relative clause)

This is the grammatical centrepiece. кото́рый is the relative pronoun "which / that / who", and like an adjective it agrees in gender and number with the noun it refers back to — here сук, which is masculine singular, so we get the masculine-singular form кото́р-. But — and this is the rule that trips everyone — its case is not inherited from сук. The case of кото́рый is decided inside its own clause, by whatever role it plays there.

Inside the relative clause the meaning is "you are sitting on it". The preposition is на ("on"), and на in a location sense governs the prepositional case. So кото́рый takes the prepositional: masculine кото́ром. The preposition sits in front of the relative pronoun — на кото́ром — exactly where English would put it in careful speech ("the branch on which you sit"), never stranded at the end the way casual English allows ("the branch you sit on").

So three independent facts converge on the single word кото́ром:

• Gender + number (masculine singular) come from сук, the antecedent.
• Case (prepositional) comes from на + location inside the relative clause.
• The whole thing is held together by на standing immediately before the pronoun.

сиди́шь — "you are sitting" (present, generic "you")

сиди́шь is the present tense, 2nd-person singular, of сиде́ть ("to sit, to be sitting"). Note сиде́ть is a 2nd-conjugation verb (сижу́, сиди́шь, сиди́т…) with the expected ж/д alternation only in the 1st-person singular (сижу́). Two things to notice:

First, сиде́ть takes its location with на + prepositional: сиде́ть на сту́ле "to sit on a chair", сиде́ть на суку́ "to sit on a branch". This is the same на + prepositional that licensed кото́ром above — the proverb simply reuses the verb's own natural construction inside the relative clause.

Second, the "you" here is generic — it addresses no one in particular, meaning "one / anyone / a person". This is the same all-purpose 2nd-person singular that runs through so many proverbs: the saying is a universal truth, not advice aimed at a specific listener. (The imperative руби́ is likewise the unmarked singular, fixed in the proverb regardless of whom you'd actually be addressing.)

Meaning and when to use it

The proverb means: don't destroy what sustains you — don't undermine your own foundation, attack your own source of support, or sabotage the position you depend on. English reaches for the nearly identical image, "don't bite the hand that feeds you", or the engineering metaphor "don't burn your bridges". The Russian image is starker: you are physically perched on the thing you're hacking through.

You use it to:

• warn someone about to harm an ally, employer, or institution they still need ("Поссо́ришься с нача́льником — не руби́ сук…");
• comment on self-defeating behaviour after the fact (someone trashed their reputation in the very field they want to work in);
• counsel restraint when feelings run hot and burning everything down looks tempting.

It is neutral in register — equally at home in conversation, an opinion column, or a manager's gentle reproach. Like many proverbs it is often clipped: the trailing «…на кото́ром сиди́шь» can be left for the listener to supply, with just «Не руби́ сук…» carrying the whole warning.

Using it in context

Vocabulary gloss

Common Mistakes

Key Takeaways

• Не руби́ is the negative imperfective imperative — the default way to forbid something in general; the perfective (не сруби́) would warn against one specific slip.
• сук is the accusative direct object, but since it is inanimate its accusative equals the nominative — no visible change.
• кото́рый → кото́ром takes its gender and number from the antecedent (сук, masc. sg.) but its case from its role inside the relative clause: на + location → prepositional.
• The preposition на stands directly before кото́ром; Russian never strands prepositions at the end.
• сиде́ть на + prepositional marks location; сиди́шь here is the generic "you" of proverbs — "anyone / one".
• Meaning: don't destroy what supports you — the Russian "don't bite the hand that feeds you"; often clipped to just «Не руби́ сук…».