Translate stream chain

Hi team, I need to translate this stream chain, in spanish we have singular and plural form to refer a past time.

Past {# [1:day][?:days]}

I need translate to: Último 1 día & Últimos ? días.
Day is simple to translate, but "Past" I need to translate to "Último" for singular form and "Últimos" for plural forms.

How can made this chain to translate correctly? Thanks a lot.