|It is simple. The equivalent of the English term "another" is not "un otro" but "otro". And same thing happens with the corresponding femenine singular (otra), femenine plural (otras) and masculine plural (otros). |
I think a lot of English speakers tend to identify "another" with "un otro", using the indefined article ("un", in this case) as a way of literal translation from English to Spanish. But remember we don't use neither "un otro" in Spanish nor any other form such us "una otra", "unos otros" or "una otras".
To have clear ideas about this, let's see some examples:
Something similar may happen with "some others", being translated as "algunos otros", which, as you may already know, is also wrong. The right form is "otros".
So, as a final note, remember: Whenever you had to translate into Spanish "another", never use the indefinite article, but just the word "otro", which must comply in gender and number with the corresponding substantive.
Hope this helps!
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