Question Words

what qué
who quién
how cómo
where dónde/adónde
when cuándo
why por qué

As their name suggest you use these words at the beginning of a sentence (or phrase) to form a question.  Because these are question words so you must always start the sentence with an inverted question mark '¿' (called a principio de interrogación) and of course you end it with a regular question mark '?' (called a fin de interrogación).

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