"He knows the value of the car."

Translation: On zna wartość samochodu.

[BrianH71]

I'm wondering why it is znać here and not wiedzieć, which is not accepted. I thought wiedzieć means to be sure of something, which would seem to agree with the meaning.

[Jellei]

It's not that easy to explain. But I think the closest way may be that "znać" is "to know X" while "wiedzieć" is "to know that X" or "to know about X".

• On zna wartość samochodu. Wie też, że go na niego nie stać. (He knows the value of the car. He also knows that he can't afford it.)

• Maria zna Paulinę. Maria wie, że Paulina jest prawniczką. (Maria knows Paulina. Maria knows that Paulina is a lawyer.)

• Znam odpowiedź na to pytanie. / Wiem, jaka jest odpowiedź na to pytanie. (I know the answer to that question. / I know, what the answer to that question is.)

• Wiem (o tym), co zrobiłeś. (I know (about) what you did).

• Wiem o tobie i twojej kochance. Znam ją z pracy. (I know about you and your mistress. I know her from work.)

[BrianH71]

Thank-you that helps.

[F4yY9kZj]

So: On wie, jaka jest wartość samochodu (?).