Interrogative quién

[cmon]

From grammar book:
Quien with accent mark is used as an interrogative word after verbs of perception such as comprender, decir, entender, saber, pensar, tener idea de, ver, etc.
Book only gives negative examples:
No sé quién llegó and No comprendió con quiénes había salido.
Does the sentence always have to be negative? And if so, would someone please explain to me at kindergarden level why that is? Would this be correct? Sé quién llegó.

No tenemos idea qué van a decidir./Tenemos idea qué van a decidir.

[Tomisimo]

I don't really have a formal explanation, but in the affirmative, you would no longer use it as an interrogative word, and thus no accent mark. Consider:

I don't know who did it.
I know who did it.

In English these look the same, but in Spanish the first one is basically

I don't know.[statement] Who did it?[question]
I know who did it.[statement]

No sé quién lo hizo.
Sé quien lo hizo

In spoken Spanish, the quién with an accent mark gets more emphasis than without the accent mark:

No sé QUIÉN lo hizo.
SÉ quien lo hizo.

I think logically this can only be used in the negative, because in the positive, it would no longer be a question and you would already know who did it.

[cmon]

Thanks

Figured as much, but I have become very dependent on you guys spelling everything out for me. Also, Babel Fish translated I know who arrived as Sé quién llegó. Not that I would ever think that Babel is the Bible.

[Tomisimo]

I'm not always right either. All that was just off the top of my head. There might be occasions when it can be used in the affirmative too. Anyone else have any ideas?

[CrOtALiTo]

I have a suggest with respect to your questions.

No tenemos idea qué van a decidir./Tenemos idea qué van a decidir.


They both have distinct meaning, but I don't understand, What do you need to know above?

[chileno]

Originally Posted by Tomisimo

I'm not always right either. All that was just off the top of my head. There might be occasions when it can be used in the affirmative too. Anyone else have any ideas?

You are right Tomisimo. At least that's the way I remember to have been taught. And I would use it like you described it.

I have been in the USA for 30 years and I had forgotten about accents etc, it is beginning to come back, although I am not so sure anymore. I used to be young too! :-)

[laepelba]

What about these examples, not in the negative, but I think that they would require the accent mark, nonetheless, right????

- Mi hermano pregunta qué haces.
- Ella quiere saber de dónde eres. (O, en Argentina y Uruguay, ella quiere saber de dónde sos. )
- El niño preguntó a qué hora saldrá el avión para Perú.

[Rusty]

Those words, without the accent mark, don't mean the same thing.
The accent mark is required when the adverb is used, and it's technically known as an orthographic accent mark.
Using the orthographic mark, you can differentiate between the conjunction que and the adverb qué, for instance. They are pronounced the same way, but have two different meanings. The word donde, without the accent is a conjunction (or a preposition).