"I have to find my keys."
Translation:Muszę znaleźć moje klucze.
You shouldn't. Polish tends to use "potrzebować" with nouns rather than verbs.
It is, of course. I meant that "Potrzebuję kluczy" sounds natural and "Potrzebuję znaleźć klucze" sounds off. By the way "Muszę klucze" is totally wrong. ;)
Maybe I misunderstood the lessons on pronouns, but since "I" am the one finding the keys and they're "my" keys, shouldn't we use swoje instead of moje?