This is the 46th most frequent Indonesian word.
selama
"Selama" means "during" or "as long as" in English.
In this sentence, 'selama' is used to indicate the duration of an event, 'the journey'.
Selama perjalanan, kami beristirahat di beberapa tempat.
During the journey, we rested at several places.
Here, 'selama' specifies the extent of time, 'two years', for which the action occurred.
Saya belajar bahasa Indonesia selama dua tahun.
I studied Indonesian for two years.
In this case, 'selama' conveys the extended period up until the current moment.