"She does not want to tell everything she knows."

Translation: Hon vill inte berätta allt hon vet.

[AbunPang]

Where would one add the addressee in? Hon vill inte berätta allt hon vet för oss?

[Arnauti]

Exactly!

[AbunPang]

Tack.

[nikozilar]

Is there a rule for when not to include "för" with "berätta"?

[Arnauti]

Yes, if you have an indirect object, i.e. if the person you're telling is mentioned in the sentence, you have för too: Jag berättade för henne I told her.
But if you just 'tell' without saying who you're telling it to, you don't have för either.

[Fizzo83]

Would it also be correct to say "...allt vad hon vet"?

[ReinerSelb]

allt SOM hon vet was accepted for me.

[muddgirl]

Why allt and not alla?

[Zmrzlina]

Allt = everything

Alla = everyone

[muddgirl]

Tack!

[RynoLawson]

Is "känner" not able to be used instead of "vet"?

[Arnauti]

No, känner could only mean feels in this context.

[matstrish]

Wait, "känner till" means know in this context.

[soundspirit]

Could you say "Hon vill inte berätta om allt hon vet"?

[GodlessGoat]

I'm wondering the same thing!
And if not, why?

[RonaldBrid1]

Why is it not
hon vill inte ATT berätta ally hon vet? Everything else so far has needed att-verb infinite

[AbunPang]

You don’t use att with modal verbs (vilja “to want”, kunna “can”, behöva “have to”, måste “must (indeclinable)”, få “may”, ska “shall”, böra “should, ought to”). In fact this is the same in English, at least with true modal verbs (those which never take the third person singular “-s” in present tense and don’t insert “do” in questions and negative sentences, such as “can” or “must”): You say “I can do that,” not “*I can to do that.”

With other verbs it depends on the verb. Some use att and some don’t and there isn’t really a hard rule for which is which. For example börja “to begin“ and sluta “to stop” are used without att: Hon börjar arbeta “She starts to work”. But fortsätta “to continue” is used with att: Hon fortsättar att arbeta. “She continues to work.”