Cuyo is an adjectival relative pronoun that you have already seen and that usually translates as “whose.” As you see below, it links two nouns and agrees in number and gender with the one it precedes:
|Madrid es una ciudad cuyas calles conocemos muy bien.||Madrid is a city whose streets we know very well.|
|Gabriela Mistral y Pablo Neruda, cuya patria es Chile, han ganado el premio Nóbel de Literatura.||Gabriela Mistral and Pablo Neruda, whose homeland is Chile, have won the Nobel Prize in Literature.|
Cuanto, when not functioning as an interrogative, may be employed as an adjective or pronoun. In the former case, it agrees in number and gender with the noun it modifies and means “all those” or “as many as”:
|Solicitaron fondos a cuantas personas pudieron.||They solicited funds from all those (as many as) they could.|
When used as a pronoun, cuanto is invariable in form and is the equivalent of “all that” or “as much as”:
|A pesar de hacer cuanto pudo, perdió el caso.||In spite of doing all he could, he lost the case.|
The above could also be expressed as A pesar de hacer todo lo que pudo… without changing the meaning.
Cuanto has a shortened form cuán, which is seen occasionally before adjectives or adverbs and is considered informal in style.
|No sabían cuán tarde era.||They didn’t know how late it was.|
acudir- to come (to the rescue), to help, to aid
añorar- to yearn for
derrocar- to overthrow, to topple, to oust
disminuir- to diminish
ignorar- to be ignorant, not to know (false friend)*
el lema- slogan
la pieza- play (theatrical), piece, room (house)
el rescate- rescue
el ron- rum
el trago- drink
desnudo- naked, nude
años + multiple of 10- a decade of _____s
*These are the traditional meanings of ignorar. Recently it has been used by some with the meaning that corresponds to the English, “not to pay attention to,” which will likely become standard in parts of the Spanish-speaking world.