-koon/-köön

Let Him Do It (-koon)

Level 4

The third-person imperative (jussive) is used for commands or wishes directed at a third party (he, she, it, or they). It is most common in formal writing, legal texts, and specific idioms like Onneksi olkoon! (Congratulations!).

How It Works

The third-person imperative, or jussive mood, allows a speaker to direct a command or wish toward someone who is not the listener, as well as toward inanimate objects, abstract concepts, or general situations.

1. Formation
Use the same stem as the second-person plural imperative: replace -kaa/-kää in lukekaa, tulkaa, tavatkaa with -koon/-köön, giving lukekoon, tulkoon, tavatkoon. Type 1 uses the strong vowel stem, but other types may use a consonant stem; do not use the present stem tapaa- for tavatkoon.

  • Singular: Stem + -koon / -köön (e.g., hän tulkoon - let him come)
  • Plural: Stem + -koot / -kööt (e.g., he tulkoot - let them come)

Note: The 1st Person Plural (Stem + -kaamme / -käämme, e.g., syökäämme - let us eat) is a distinct formal imperative form, not a 3rd person form.

2. Passive Jussive
The passive imperative (e.g., tehtäköön - let it be done, sanottakoon - let it be said) is formed by adding -koon / -köön to the strong passive stem ending in -ta/-tä or -tta/-ttä: tehtä- + -köön, sanotta- + -koon. It is common in formal resolutions and legal language.

3. Usage and Nuance
In modern speech, these forms are especially familiar in fixed expressions and expressions of permission or resignation:

  • Set Phrases: Onneksi olkoon! (Congratulations!), Eläköön! (Long live!), Olkoon menneeksi (Let it be/Fine).
  • Resignation: Expressing that someone can do what they want (e.g., Menkööt jos haluavat - Let them go if they want).
  • Formal Wishes: Used in blessings (e.g., Jumala varjelkoon - God forbid! / God protect [us]).

4. Negation
Negation uses the special auxiliary verb älköön (singular) or älkööt (plural) followed by the connegative form ending in -ko/-kö.
Example: Älköön kukaan tulko sisään. (Let no one come in.)
For the passive jussive, negation uses älköön + passive connegative (e.g., Älköön tehtäkö - Let it not be done / It shall not be done).

5. Object Rules
Unlike the 2nd person imperative, the active 3rd person imperative follows ordinary active-clause object rules. For a total object:

  • Singular nouns: Take the genitive -n (e.g., Hän ostakoon auton).
  • Plural nouns: Take the nominative plural -t (e.g., He ostakoot autot).
  • Personal pronouns: Take the accusative -t (e.g., Hän valitkoon minut).

Negative clauses and other partitive-object contexts still use the partitive. The passive jussive follows the passive object rule, meaning a noun total object is in the nominative case (e.g., Tehtäköön se, not Tehtäköön sen).

Exclamations
Hitto soikoon! and Piru vieköön! are familiar mild swears, roughly “Damn it!” Their fixed wording does not make free use of the jussive equally natural in every conversation.

Examples (5)

  1. Onneksi olkoon!

    Congratulations!

    Word by Word: For fortune let it be!

    This is the most common everyday use of the jussive mood, using the verb 'olla' (to be).

  2. Jos he haluavat lähteä, menkööt.

    If they want to leave, let them go.

    Word by Word: If they want to leave, let them go.

    Here, the plural form 'menkööt' expresses resignation or indifference toward the third party's actions.

  3. Hän ottakoon tämän kirjan.

    Let him take this book.

    Word by Word: He let take this book's.

    Note that the object 'kirjan' is in the genitive case, which is a key difference from the 2nd person imperative.

  4. Tulkoon mitä tulee.

    Come what may.

    Word by Word: Let come what comes.

    A common idiomatic expression using the jussive to show acceptance of future events.

  5. Älköön kukaan unohtako tätä päivää.

    Let no one forget this day.

    Word by Word: Let not no one forget this day.

    Demonstrates the negative singular form 'älköön' followed by the connegative 'unohtako'.

Common Mistakes

  • Using the nominative for a singular total object.

    Hän ottakoon kirja.
    Hän ottakoon kirjan.

    Unlike the 2nd person singular imperative (Ota kirja!), the 3rd person imperative follows standard indicative rules: a singular total object takes the genitive -n.

  • Using the weak stem instead of the strong stem.

    Hän luekoon kirjan.
    Hän lukekoon kirjan.

    For type 1 lukea, use the strong vowel stem luke-, as in lukekaa → lukekoon. This is not a universal present-stem rule: compare tulla → tulkoon and tavata → tavatkoon, using the plural-imperative stem.

  • Using the jussive when you mean 'he will probably come'.

    Different MeaningHän tulkoon huomenna.
    Hän tullee huomenna.

    'Hän tulkoon huomenna' is a good sentence, but it means 'Let him come tomorrow.' The jussive (-koon) expresses a wish or a command. The potential mood (-ne-) expresses probability: 'Hän tullee huomenna.'

How It Connects

Tap a pattern to see what it builds on and what it leads to.

-koon/-köönLevel 4Let Him Do It (-koon)

Learn This First

To understand the third person imperative (-koon), you need to be familiar with vowel harmony to choose the correct suffix. It is also helpful to understand the plural imperative, as both are formed from the same verb stem (the 'strong' stem) and use the -k- marker. Knowledge of third-person vowel lengthening helps in recognizing the structure of the ending.

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Patterns that build on this one.