kennen or kunnen? And where weten fits

English uses know where Dutch divides the work between kennen and weten, and Dutch also keeps kennen apart from kunnen (can, be able to): Ik ken onze nieuwe buurvrouw. (I know our new neighbour.), Ik kan de afspraak verzetten. (I can reschedule the appointment.), and Ik weet waarom de balie dicht is. (I know why the desk is closed.). The words after the verb give you the best clue.

Use kennen for familiarity with a person, place, thing, or learned material; use kunnen for ability or possibility; use weten for a fact, an answer, or the content of a clause.

1. Look for a person, place, thing, or material someone has learned. Choose kennen: Wij kennen die route. (We know that route.)
2. Look for another verb in the infinitive, or for the meaning ‘possible’. Choose kunnen: Noor kan de kraan repareren. (Noor can repair the tap.); Dat kan morgen. (That is possible tomorrow.)
3. Look for a fact, an answer, or a clause beginning with dat, of, or a question word. Choose weten: Hij weet het antwoord. (He knows the answer.); We weten waar de sleutel ligt. (We know where the key is.)

The shortcut ‘noun means kennen’ is not mechanical. An answer is information, so Dutch says Ik weet het antwoord. (I know the answer.), not ik ken het antwoord. Ask what kind of complement and meaning you have, not only which part of speech comes next.

A bare language name is learned material and therefore takes kennen: Mina kent een beetje Turks. (Mina knows a little Turkish.). If you name the skill, use kunnen plus an infinitive: Mina kan Turks lezen. (Mina can read Turkish.). The shortened Mina kan Turks occurs in speech, but it is not the standard pattern taught for careful writing.

In the western Netherlands, including the Randstad, you may also hear forms of kennen and kunnen mixed in everyday speech. Recognise that variation, but keep the standard complement-based distinction in an exam or a formal text.

• Use kennen for people and familiar things: Kent u mijn collega? (Do you know my colleague?); Ik ken dat gebouw. (I know that building.)
• Use kennen for material you have learned: De cursisten kennen de nieuwe woorden. (The students know the new words.)
• Use kunnen before an action: Kun jij deze brief vertalen? (Can you translate this letter?)
• Use kunnen for possibility even without a second verb: Een afspraak om elf uur kan ook. (An appointment at eleven is possible too.)
• Use weten for information: Zij weet dat de winkel gesloten is. (She knows that the shop is closed.); Weet je wanneer de bus komt? (Do you know when the bus arrives?)

Do not put kennen before an infinitive: use Ik kan zwemmen. (I can swim.), not ik ken zwemmen. Do not use weten for familiarity with a person: use Ik ken de huisarts. (I know the GP.). With a language, either name the learned material with kennen or name the skill with kunnen + infinitive.

Review modal verbs, the bare infinitive, and common irregular verbs. The page on indirect-question order explains the clauses that often follow weten.