1 used with prepositions to mean that time in the past or future -- waktu itu
2 after that -- kemudian
3 in that case -- kalau begitu
He might not give us the money and then what would we do?
4 often used especially at the end of sentences in which an explanation, opinion etc is asked for, or which show surprise etc -- lalu
What do you think of that, then?
5 also; in addition -- juga