sexto período
You would say "el sexto" or "la sexta".
El seis de enero
Sixth.
sixth .
i think you mean sexto which translates to sixth as to sixth caller
cuando estaba en sexto grado, empecé a aprender cosas nuevas
sixth = sexta hour = hora sexta hora
In Spanish, sixth is sexto (singular, masculine). If you wish to make in singular and plural, use sexta. To make either form plural, simply add an s at the end.
It depends, if you are trying to impress someone then no. But anyway you are in sixth grade that's when you start.
Yo estoy en sexto grado. I am in sixth grade.
Sister in law in Spanish is cunada.