either

• Adverbio o conjunción que se usa para añadir información en contextos negativos (por ejemplo, «a mí tampoco me gusta») o para presentar una alternativa entre dos opciones (por ejemplo, «puedes o irte o quedarte»).

An adverb used to add information in negative contexts (e.g., “I don’t like it either”) or to indicate an alternative in a pair of choices (e.g., “You can either go or stay”).

1. Choice between alternativesA2formal

   Indicates that one of two possibilities is selected or possible.

   elección entre alternativas

   • You can either take the bus or walk to the station.
   • Either you finish the report today, or we will delay the project.
   • She will either call us back or send an email.
   • We can either start now or wait for the manager.

2. Also (in negative constructions)A2informal

   Used in negative statements to mean ‘also not’ or ‘as well’, adding agreement with a previous negative.

   tampoco (en negaciones)

   • I don’t like broccoli, and my brother doesn’t either.
   • She hasn't finished the assignment, and Tom hasn’t either.
   • We couldn't find the keys, and nobody else could either.
   • He isn’t coming to the party, and I’m not either.

   Sinónimosneither

• Como determinante, 'either' se usa con un sustantivo singular para indicar una de dos opciones, enfatizando cualquiera de las dos posibilidades.

Either as a determiner is used before a singular noun to refer to one of two options. It emphasizes any one of the two possibilities.

1. one of two people or things when it is not important whichB1formal

   Refers to one member of a pair of people or things, where the specific choice between the two is irrelevant or interchangeable. It signals that both options are equally acceptable, and selecting either one fulfills the condition. The focus is on the freedom to pick any one from the two without consequence or preference.

   cualquiera de los dos

   • "Would you like red or white wine?" - "Oh, either."
   • Ask Dom or Andrew, either of them will help you.
   • Do either of you girls want a drink?

2. B2formal

   Refers to each of two people, things, or sides, emphasizing that a statement applies to both members of a pair equally. Often used with spatial expressions (e.g., either side, either end) or in formal contexts to indicate that something is true for both options simultaneously. Unlike the selective meaning of "either", this usage highlights duality and inclusion of both elements rather than a choice between them.

   cada uno de los dos

   • People were smoking on either side (= at both sides) of me.
   • You can use the train or the bus, either way it'll take an hour.