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"Whether" is a conjunction which is often translated as "si", and "should" is an auxiliary verb which is often translated as "deber". Learn more about the difference between "whether" and "should" below.
whether()
A conjunction is a word that connects words, phrases, clauses, or sentences (e.g., The cat and the dog slept.).
a. si
I don't know whether I am going to do it today or tomorrow. No sé si lo voy a hacer hoy o mañana.
a. si
I'll try to find out whether she's at the office.Voy a tratar de averiguar si está en la oficina.
a. no direct translation
The following examples show ways to translate this word or phrase without using a direct equivalent.
Alicia has made up her mind - she'll resign, whether or not she gets this other job.Alicia se decidió: va a renunciar, consiga o no el otro trabajo.
Whether you like it or not, I will buy this shirt.Te guste o no, me voy a comprar esta camisa.
should()
An auxiliary verb, or helper verb, is a conjugated verb that comes before a main verb and determines the main verb's tense, mood, or aspect (e.g., I have gone.).