According to the Collins Dictionary's definition, if something happens every other day or every second day, it means that it happens one day, then does not happen the next day, then happens the day after that, and so on. If I see my friend today, then tomorrow a one-day-break, then the day after tomorrow I see her and it continues the same way, which of the following sentences can I use interchangeably to describe this situation?
1) I see my friend on alternate days.
2) I see my friend every other day.
3) I see my friend every second day.
4) I see my friend every third day.