You probably love that there are no verb tenses, no genders, and no plural forms to memorize in Indonesian.

But then you discover affixes.

In Indonesian, these are called imbuhan.

What are Indonesian affixes?

Think of an Indonesian word like a building block. The main block is the Base Word (Kata Dasar). Affixes are extra little pieces you stick onto the front, back, or both sides of that block to change its shape and purpose.

For example, take the word jalan (walk/street).

• Add a prefix: Berjalan (To walk)
• Add a suffix: Jalanan (The road/path)
• Add a circumfix (front and back): Perjalanan (A trip/journey)

You don’t need to memorize every single rule right now.

In this guide, I’ll break down the most common affixes so you can start using them today.

Understanding the base word (kata dasar)

Before we stick things onto words, we need to know what the word is.

The Kata Dasar is the root word found in the dictionary. In daily, informal conversation with friends, we often just use the base word without any affixes.

For example, makan means “eat”.

However, when we want to be grammatically correct, specific, or formal, we need affixes to tell the listener exactly what is happening.

The prefix Ber- (having or doing)

The prefix Ber- is one of the first you will learn. It is usually placed in front of verbs or nouns.

Generally, Ber- creates a verb that does not need an object (intransitive). It often means “to have,” “to wear,” or “to do.”

Here are common examples:

• Keluarga (Family) -> Berkeluarga (To have a family)
• Kacamata (Glasses) -> Berkacamata (To wear glasses)
• Bicara (Speak) -> Berbicara (To speak)

You usually use this when the subject is doing something, but not necessarily to someone else.

The active prefix MeN- (doing an action)

This is the big one. This is the affix that confuses learners the most because it changes its spelling depending on the word it attaches to.

The MeN- prefix turns a base word into an active transitive verb. This means the subject is doing the action to an object.

Why is the ‘N’ capitalized? Because the sound changes! It can become Mem-, Men-, Meng-, Meny-, or just Me-.

Here is a simple table to help you remember the sound changes:

*Note: For the letters K, T, S, and P, the first letter of the base word usually “melts” or drops away. For example, Tulis (write) becomes Menulis (not Mentulis).

The passive prefix Di- (done by)

If MeN- is active, Di- is passive. The good news? Di- is very easy.

You simply put di in front of the base word. Nothing changes. No letters drop.

This focuses the sentence on the object rather than the subject. It is the equivalent of saying “is eaten,” “is bought,” or “is written” in English.

Formula: Object + di-[verb] + (oleh) + Subject.

The suffix -an (making nouns)

This is a very useful suffix. When you stick -an to the end of a verb, it usually turns that verb into a noun. Specifically, it turns it into the result of the action or the object of the action.

Common examples:

• Makan (To eat) -> Makanan (Food)
• Minum (To drink) -> Minuman (Drink/Beverage)
• Tulis (To write) -> Tulisan (Writing/Handwriting)
• Pikir (To think) -> Pikiran (Thought/Mind)

Regional variations and slang (Jakartan style)

I always tell my students that textbook Indonesian and “street” Indonesian can sound like different languages.

If you are visiting Jakarta or watching Indonesian movies, you will notice people don’t always follow the rules above.

In informal, colloquial Indonesian (often heavily influenced by Javanese and Betawi dialects), we change the affixes to make them shorter and faster to say.

1. Dropping the ‘Me-’ Instead of using the full MeN- prefix, colloquial speakers often just use the nasal sound (N/M/Ng/Ny) or use Nge-.

• Formal: Saya mengerti (I understand).

• Informal: Aku ngerti.

• Formal: Dia menulis (He writes).

• Informal: Dia nulis.

• Formal: Kita minum (We drink).

• Informal: Kita ngeminum (or just minum).

2. The ‘-in’ suffix This is the most famous Jakarta slang trait. Instead of using the formal suffixes -kan or -i (which are used to make causal verbs), people use -in.

• Formal: Hidupkan lampu (Turn on the light).

• Informal: Hidupin lampu.

• Formal: Pikirkan itu (Think about that).

• Informal: Pikirin itu.

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Affixes act as the glue that holds Indonesian sentences together. While there are more complex ones (like Ke-an, Pe-an, and Ter-), mastering the four basic types above will help you navigate 80% of daily situations.

Remember:

• Ber-: Doing/Having (No object needed).
• MeN-: Active action (Needs object, dropping letters KTSP).
• Di-: Passive action (Object comes first).
• -an: Turns verbs into nouns.

Don’t stress about memorizing the table perfectly. The more you listen and read, the more these sounds will become natural to your ear.