This is the 38th most frequent Portuguese word.
todos
"Todos" means "everyone" or "all" in English.
In this sentence, the word 'todos' is used as a pronoun to indicate 'all' referring to the group of students collectively.
Todos os alunos compareceram à aula hoje.
All the students attended the class today.
Here, 'todos' is used in combination with 'os' and 'dias' to express 'every day,' referring to the general occurrence of days during the week.
Eu trabalho todos os dias durante a semana.
I work every day during the week.
In this case, 'todos' is used as a pronoun to indicate 'everyone,' referring to all individuals addressed by the teacher.