Spanish language Q&A Forum

"-¿A ________ vamos a ver esta noche? -A Luis y Gerardo."

I wrote 'quién' because I thought the questioner wouldn't necessarily know that they would be seeing more than one person. That answer was marked wrong.  Would we normally use the plural when asking about an unknown number of persons?

EDIT: I just looked at the question again and see that there was a hint (which I managed to miss) about which PLURAL to use,  but my question about which we would normally use still stands.

I encountered this in a video:

John es estudiante. Roger es UN estudiante también. 

Why does the article appear when también is added? Is this correct?  If so, what is the explanation?

(Google translate also adds the indefinite article when también is used.)

A esto libro le faltan dos paginas. I found this sentence and him confused why we use a with it

This was an excellent lesson - topical of course, but so easy to follow because of the perfect diction. Gracias. John

Can I use debo instead of debería? For example: 

"con todas las velas?" Right now it says "todas la velas"

In the lesson on 'Para mí que'  it gives its use as -  'we simply express having a feeling, an inkling about something happening' 

The English text here says 'What amazes me...'  Surely that's stronger than an inkling!

It also says 'esta sigue siendo un medio de lo más popular'  Why isn't it 'este' as it refers to the masculine word medio

Gracias

Please explain on what basis cuándo is correct here and not cuando. This looks to me like a perfectly straightforward statement of fact. No one is asking a question. In fact, this sentence is an answer to a question such as, "When will you see him again?" 

No entiendo por qué el Rey hizo eso. Él lo hizo porque quiso

Unless the Spanish have a definition of "conjunction" that differs from the one I've always understood, both "por qué" and 
"porque" are both being used as conjunctions in those sentences. It is the sense of their use which differs.

Can these two uses be distinguished in spoken Spanish and if so, how?

"Spanish online reading and listening practice - level A1 " but I think it should say A2.