How to ask questions in Spanish

Question	Meaning	Example
¿Cómo ..?	how ..?	¿Cómo está? = How are you? ¿Cómo se llama? = How do you call yourself? (or what's your name?) ¿Cómo se apellida? = How are you surnamed? (or what's your surname?) ¿Cómo es su mujer? = What's his wife like? ¿Cómo se va al centro de ..? = How does one get to the centre of ..? (the use of 'one' doesn't sound posh in Spanish) ¿Cómo dice? = Pardon? (or you can just say ¿cómo?) In colloquial speech, this is sometimes used with anger or fustration, meaning something like "how come ..?" ¿Cómo dejaste el móvil en el tren? = How come you've left your mobile on the train?
¿Cuál ..? ¿Cuáles ..?	which ..?	This means 'which' but it is sometimes translated as 'what' in English (because English uses the word 'what' in certain questions) but it's real meaning is 'which'. Which (cuál) replaces 'what' (qué) when the listener knows the things that you are referring to. Cuáles is the plural of cuál and is used with plural things e.g. ¿cuáles libros? = which books? Conozco a su amigo. ¿A cuál? = I know your friend. Which one? Technical bit: Dont worry if you don't understand this explanation yet. The 'a' here is the "personal a" used in front of a person that is the object of a verb. Usually, whenever you want to say 'what is', you say "¿cuál es ..?" or the plural "cuáles son ..? = which are ..?" ¿Cuál es su nombre? = Which is your name? (or what is your name?) Think: "Which (out of all the names) is your name?" ¿Cuál es su profesión? = Which is your profession? (or what's your profession?) Think: "Which (out of all the professions) is your profession?" But if you are asking for a definition, you use qué: ¿Qué es un tractor? = What's a tractor? Also - ¿Qué hora es? = What time is it? (la hora = the hour) Beginners may be confused which word to use if they want to start a question with 'what'. If you are asking which of a possible range of things, then use cuál: Hoy he visto tres coches, pero todavía no he decidido cuál voy a comprar = Today I've seen three cars, but still I haven't decided which I'm going to buy ¿Cuál es la diferencia entre un presidente y un primer ministro? = What's the difference between a president and a Prime Minister? ¿A cuáles de los profesores se ha enviado un correo electrónico? = To which of the teachers have been sent an email? (notice the insertion of 'se' here because you aren't referring to anyone, you are not saying "to which of the teachers have YOU sent an email? - it is like saying "se puede hacerlo = one can do it", "puede hacerlo = you can do it") You could also translate that sentence as: To which of the teachers has one sent an email? (the use of 'one' here doesn't sound posh in Spanish) Compare these questions: ¿Cuál desea? = Which (one) do you desire? (when you and the listener knows which things you are referring to e.g. cakes or drinks) ¿Qué desea? = What do you desire? (now anything is possible, you don't know what the listener wants) Cuál isn't used as an adjective (technically, it is called an "interrogative pronoun", a pronoun used in questions and indirect questions but don't worry if you don't understand what that is yet) In Spain use qué instead in front of an object: No había decidido qué coche comprar = He hadn't decided which car to buy (in this example, some places in Latin America would use cuál here). ¿Qué cosas me darían? = What things would they give me?
¿Cuándo ..?	when ..?	¿Cuándo sale el último tren para ..? = When is the last train for ..?
¿Cuánto ..?	how many ..?	Notice that this word sounds like 'quantity'. This is an adjective so it can change to a plural or a femine adjective so you may hear at a hotel: ¿Para cuántas noches? = For how many nights?
¿Dónde ..?	where ..?	Note that there is a special word - adónde which is a contraction of the word 'a' and 'dónde' meaning 'to where ...? ¿A dónde vamos? = Where are we going to? (literally: to where we go?) ¿A dónde va ese tren? = Where is that train going to? (literally: to where goes that train?) ¿de dónde es usted? = where are you from? (literally: from where are you?) ¿por dónde se va al cine? = how do you get to the cinema? (literally: by where does one go to the cinema?) ¿Dónde se puede cambiar dinero? = Where can one (where can I) change money? ¿Dónde están los aseos / servicios? = Where are the toilets? Indirect question - "no recuerdo dónde vi a su amigo" = "I don't remember where I saw your friend"
¿Para qué?	what for? For what purpose?	¿Para qué lo quiere? = Why do you want it? (for what purpose do you want it) para qué literally means "for what?" and is short for "for what purpose?" This is because without 'que', para can mean 'in order to' Lo quiero para ayudarme = I want it (in order) to help me (or I want it for the purpose of helping me)
¿Por qué ..?	why?	Don't get this confused with porque = because ¿Por qué? = why? ¿Por qué lo necesitamos? = why do we need it? ¿Por qué te lo dio tu amigo? = Why did your friend give it to you? (notice that the verb is in front of the subject because it is a question)
¿Qué ..?	what ..?	This means 'what' but it is sometimes translated as 'which' in English (because English uses the word 'which' in certain questions). This is used when you haven't identified what something is: ¿Qué autobús va a ..? = Which bus goes to ..? (literally: what bus - a bus that is unidentified) ¿De qué andén sale? = From which platform does it leave? = (literally: from what platform does it leave?) ¿Qué tiene en la mano? = What have you in your hand? (you say 'the hand' because it is obvious you meant 'your hand' although you could say 'su mano' if you wanted). This is also used before an unchanged verb (the infinitive): No sé qué hacer = I don't know what to do See cuál for more information about the difference between cuál and qué. Also use this when you reported a question: me preguntó qué tenía en la mano = she asked me what I had in my hand Note that in exclamations, qué is used for "what a ..!" ¡Qué disorden! = What a mess! or exclaming "WHAT!" = ¿Qué? but "what did you say?" is ¿Cómo? (you can thank Manuel from Faulty Towers for that bit of confusion) Also you can exclaim in a disbelief, qué without an accent - ¡que no hay pan! = what, no bread!
¿Quién ..? ¿Quiénes ..?	who ..?	Quiénes is used when you know that there are more than one person. ¿Quién es él? = Who is he? ¿Quiénes lo compraron? = Which persons bought it? I just want to point something out. Notice when you want to translate these: I know who is going to win. I do not know who is going to win. In this case you must say "Sé quién va a ganar. No sé quién va a ganar" since you mean that you know the answer to the question "who is going to win?" but if you want to say "I know (personally) the man that is going to win" you must say "Conozco (personalmente) al que/a quien va a ganar" because these are not indirect questions, they are just factual statements.

I've just asked a friend about this last point and they said:
[Original text - translated below]
Se puede decir de las dos maneras.
En la primera opción: No sé lo que quieres. Se refiere a a algo que quiere y desconoce al mismo tiempo, pero refiriendose a un objeto, ya sea material o no.
Mientras con "qué", sería: No sé qué quieres. Se refiere a que desconoce lo que quiere, pero refiriéndose a una pregunta. Es decir, el "qué" acentuado es cuando se cuestiona una pregunta. El "que" sin acentuar no cuestiona ninguna pregunta, acompaña al verbo que presenta una actitud predominante.
Ejemplos:
- ¿Qué es aquello que veo?
En este caso, te encuentras dos: "qué" y el "que". El primero se refiere a una pregunta y el otro acompaña al verbo. El verbo es el predominante y el "que" pasa a ser secundario. El "qué" pasa a ser predominante en la frase.

[My translation]
It can be said either way.
In the first option "no sé lo que quieres" refers to something that you want but you fail to recognize what it is at the same time whilst referring to an object that may or may not exist.
However, with "qué" it would be "No sé qué quieres" which refers to something that you fail to recognize what you want, but refers to a question (an indirect question). It is to say the "qué" (with an accent) is when one asks a question. The "que" without an accent does not refer to any question and makes a subordinate clause.
Examples:
¿Qué es aquello que veo? = What is that I see?
In this case, you find both "qué" and "que". The first refers to a question and the other accompanies a verb.
Basically, this means "que" means "that", "qué" is an indirect question. "No sé lo que quieres" means "I don't know what you want" and refers to something that may or may not exist. "No sé qué quieres" means the same thing but is asking the indirect question "what do you want?"

How to ask questions in Spanish

Translating "what"