Learn Hardcore Dutch: Ik kan mijn sleutel niet terugvinden.

Dutch main clauses follow the V2 rule: the finite verb (kan) occupies the second slot. Everything else—objects, adverbs, and non-finite verbs—fills the other positions. Because terugvinden is an infinitive (attached to the modal kan), it gets “pushed” to the clause’s end as part of the verb cluster.

Why is niet placed before terugvinden, rather than after mijn sleutel?

In Dutch, niet usually precedes the element or phrase it negates. Here you want to negate the act of finding your key again, not the possession of the key. So niet goes immediately before the infinitive terugvinden. If you said Ik kan niet mijn sleutel terugvinden, you’d imply “I can’t find my key, but I can find something else,” shifting the focus of the negation.

Why is terugvinden written as one word here, when I sometimes hear “vind… terug”?

terugvinden is a separable verb (terug- + vinden). In the infinitive form (especially after modals like kan), the parts stay together as one word. In simple present or past without a modal, the prefix detaches:

“Ik vind mijn sleutel niet terug.”
“Hij vond zijn pet terug.”

What’s the difference between vinden and terugvinden?

vinden simply means “to find.”
terugvinden means “to find again” or “to retrieve something lost.”
Using terugvinden emphasizes that you’re trying to recover an item you once had but can’t locate now.

Could I say Ik vind mijn sleutel niet terug instead of Ik kan mijn sleutel niet terugvinden?

Yes. “Ik vind mijn sleutel niet terug” is the simple present of the separable verb terugvinden without a modal. It means the same thing. When you add a modal like kan, you switch to the infinitive form and move it to the end: Ik kan mijn sleutel niet terugvinden.

Why do I use mijn instead of an article like de before sleutel?

Possessive pronouns (mijn, jouw, zijn, etc.) replace the definite or indefinite article. You can’t say de mijn sleutel; you choose between “de sleutel” (the key) or “mijn sleutel” (my key). Here you want to specify ownership, so you use mijn and drop de.

If I want to replace mijn sleutel with a pronoun, what do I use?

You’d use hem, because sleutel is a common-gender noun (a “de-word”). So the sentence becomes:
Ik kan hem niet terugvinden.

Could I use hervinden instead of terugvinden?

Yes, hervinden also means “to find again,” often in a more formal or abstract sense (e.g. “himself” or “one’s path”). For everyday lost objects, terugvinden is far more common.