I hope this is help you.
1st person singular = I = Aku , prefix"ku"
1st person plural = We = Kami, Kita there is no prefix for kami and kita
example :
- this is our book, Jane. Ini buku (milik) kita, Jane.
2nd person singular = You, prefix "mu"
2nd person plural = Kalian , and there is no prefix for "Kalian"
3rd person singular = He/She = Dia , prefix "nya"
3rd person plural = They = Mereka , i think you should use "mereka"
example :
This book belongs them
Buku ini milik mereka