“AKU” means I, or me, or my in English. Basically, AKU is the synonym of “SAYA” and used as the pronoun of a first person in a conversation.
Basically, both are interexchangeable and can be used to replace each other. However, Indonesian prefers to use “SAYA” than “AKU” in daily conversation. One of the reason because “SAYA” sound more neutral and humble.
AKU can be used as a subject, object, or as a possessive pronoun. One of the difference from “SAYA” is that “AKU” changes form whenever it is used to show possession and may be attached to a verb whenever used as an object.
As a Subject : placed at the beginning of a sentence
- Aku makan nasi – I eat rice
- Aku pergi – I go
As an Object : behind a verb or attached to
- Pukul aku ! – Hit me !
- Ia memberiku sebuah buku – She gives me a book
If we use “SAYA”, the 2nd sentence is “Ia memberi saya sebuah buku” (SAYA doesn’t change)
As a possessive pronoun : attached to a noun
- Bajuku berwarna hijau – My shirt is green (Baju = Shirt)
- Mobilku Nissan Serena – My car is Nissan Serena (Mobil = Car)
As an alternative, you can say also “bajuku = baju saya” or “mobilku = mobil saya”.