This article about the 10 most important grammar rules in Bahasa Indonesia (Indonesian) is a complement to my guide: How I learned Bahasa Indonesia in 1 Month.

By learning these rules, you should improve your conversational skills significantly without putting in too much effort.

I'm not a native Indonesian speaker so if you think I wrote something wrong, please don't hesitate to leave a comment.

Placing words in the right order in Indonesian
Most of the time, you can place words in the same order as you would in English: Subject + Verbs + Object.

There are a few exceptions though:

Personal pronouns:
They are placed after the noun. For instance: "Your cat" = "Kucing kamu" (literally "Cat you")

They are also placed after the noun. For instance: "New car" = "Mobil baru" (literally "Car new").

Talking about a future event in Indonesian
As you may know, there are no tenses in Indonesian. Therefore, you need to use specific adverbs or dates if you want to talk about a future event.

This is the most common way to talk about something that will happen in the future. It is a bit formal though and you can omit the word in some conversations as long as there is a time marker (see below).

This verb (meaning "to want") is often used to replace "akan" in informal conversations.

Example: "He will graduate in 2020"
→ Dia akan lulus tahun 2020
→ Dia mau lulus tahun 2020

About time markers:
Time markers are adverbs or sentences that indicate the time or date of an event: Two of the most common are:
→ "Besok", meaning "Tomorrow" but also, confusedly, "Later after today" or "Next".
→ "Nanti" meaning "Later".

After "Nanti", you can add a more precise timing if you can: "Nanti malam" ("Later tonight"), "Nanti sore" ("Later this afternoon") or "Nanti jam 2" ("Later at 2PM").

Talking about a past event in Indonesian
There is no past tense in Indonesian. Instead, time markers are used to indicate that the action occurred in the past:

→ "Kemarin", meaning "Yesterday" (or "Before yesterday"). For instance: "Kemarin, saya nonton movie" = "Yesterday, I watched a movie" (literally, "Yesterday, I watch movie").
→ "Pernah", meaning "Once" or "Ever". For instance: "Aku pernah cinta sama dia" = "I once loved her".
→ "Telah" or "Sudah", meaning "Already" or "Just". For instance, "Saya sudah makan" = "I just ate" (literally, "I just eat").
→ "Tadi", meaning "Just before" or "A short while ago". For instance, "Tadi, saya bertemu sama teman" = "Just before, I met with my friend" (literally, "Just before, I meet with my friend").
→ "Dulu", meaning "Before". For instance, "Dulu, aku suka main futbol" = "Before, I used to like playing football" (literally, "Before, I like to play football").
→ "Baru", meaning "Just" when placed before a verb. For instance, "Aku baru makan" = "I just ate" (literally, "I just eat"). "Baru" can also mean "New" when used as an adjective.
→ The expression "Yang lalu", which could be translated as "Ago". For instance, "5 years ago" = "5 tahun yang lalu"
→ An exact date. For instance, "I was born in 1990" = "Saya lahir tanggal 1990".

Talking about events happening now in Indonesian
Two words are used to talk about current events (present continuous in English):

Lagi is the most used in informal conversations. Placed before the verb, it generally describes a short action (eating, watching a movie, going shopping, etc). For instance, "I'm eating" = "Aku lagi makan"

Sedang is more formal and it can be used for both short and long actions (learning a language, studying, working in a company). It is also placed before the verb. For instance, "Saya sedang cari kerja" = "I'm searching for a job".

Giving a date and the time in Indonesian
How to express the time or a date is different in English and in Indonesian. In the latter, before the time marker, you must add a noun to specify what the marker is about. For instance:

Jam + numerical. Example: "Jam 3" = "3 o'clock"

Hari + day. Example: "Friday" = "Hari Jumat"

Bulan + month. Example: "November" = "Bulan November"

Tahun + year. Example: "2017" = "Tahun 2017"

Specific date:
Tanggal + date. Example: "January 10th" = "Tanggal 10 Januari"

Using prefixes and suffixes in Indonesian
Many words in Indonesian are formed from a root word - verb, noun, adjective - to which a suffix or a prefix is added (sometimes both).

Those suffixes and prefixes modify the meaning to the root word according to specific rules. If you learn these, you will be able to improve your vocabulary significantly.

Based on my experience, this is the hardest part of learning Indonesian grammar. As a beginner though, you only need to understand the concept and to be able to recognize when there is a prefix or a suffix.

These are the most common prefixes:

Ber-: Usually, it is added to a noun, a verb or an adjective to form a verb whose meaning is "Having the attributes of...".
Example: Berkacamata = To wear glasses (from "kacamata" = "glasses").

Men-: Most often, it is added to a noun, a verb or an adjective to form a verb whose subject is actively doing something.
Ex: Mengajar = To teach (from "ajar" = "teaching").

Nge-: A very informal way to create verbs from nouns or adjectives. It is popular among young people to adapt English words to Indonesian.
Ex: Ngebeer = to drink beer, Ngechat = to chat, Ngecharge = to charge a phone, Ngegym = to go to the gym, etc.

Pen-: Generally, it is added to a noun, an adjective or a verb to form the noun of a person doing/or being as the root word.
Ex: Pemalu = A shy person (from "malu" = "shy").

Ter-: The easiest one, it is a superlative that can be translated by "the most":
- "Terkenal" = "The most famous" (literally, "the most known")

Di-: Adding "Di" before a verb is how to form the passive voice in Indonesian.
- Dipegang = to be grabbed (from pegang = to grab)

These are the most common suffixes:

-nya: A very common and useful suffix that you can add to a noun. It means "its", "his", her" or "the".
Ex: Mobilnya = "His car", "her car" or "the car", depending on the context (from "mobil" = "car").

-an: It is added to a verb or to an adjective to form a noun.
Ex: Makanan = Food (from "makan" = "to eat")

-kan: It is often added at the end of a verb, an adjective or a noun to form a transitive verb. In particular, it is used when something is done for the benefit of another. It is also used to give orders.
Ex: Matikan lampu! = Turn off the light (from "mati" = "dead")

To know more about suffixes and prefixes, you can also read this excellent page:

Plural in Indonesian
You may have read that to form a plural in Indonesian, you can just say any word twice. For instance, to say "kids", you can say "anak-anak" (from "anak" = "a kid").

This is not completely true. Doubling a word does not always work. It is adequate to translate an expression like "a bunch of", but it is better to avoid in any other cases. In most informal speeches, the best thing to do is to leave the word as it is. Your interlocutor should understand if there is a plural from context alone. To help with that, you can use numbers or adverbs like "banyak" (a lot) or "beberapa" (several).

Asking questions
The easiest way to ask yes-no (or closed) questions in Indonesian is to add a question mark at the end of a sentence. For instance: "Is he cooking?" = "Dia lagi masak?" (literally "He is cooking?").

You can also start your sentence with the formal "Apakah", or its shortened version "apa". For instance, "Is he your older brother?" = "Apa (kah) dia kakak kamu?". "Apakah" means "Is..." or "Are...".

When using an interrogative pronoun such as "Apa" ("What"), "Berapa" ("How many"/"How much"), "Bagaimana" ("How"), "Siapa" ("Who"), etc, you can place it either at the end or at the beginning of your sentence.

A major difference with English is that the word "Apa" (What) cannot be used with people's name or numbers. To translate "What is your name?", you cannot say "Apa nama kamu?" (literally: What name you?) but "Siapa nama kamu ?" (literally, Who Name You). Similarly, to translate "How old are you?", you cannot say "Apa umur kamu?" (literally, "What age you?") but "Berapa umur kamu?" (literally: "How much age you?").

Note that the interrogative pronoun "apa" and the shortened version of apakah, "apa", are two different words with different meanings. 

Saying No in Indonesian
Negation can be expressed by different means in Indonesian.

→ In formal speeches, you will use "Bukan" in front of a noun or a pronoun, and "Tidak" in front of an adjective or a verb.

For instance:
Kamu bukan ayah aku = You are not my dad
Aku tidak mau keluar = I don't want to go out

→ When speaking informally to friends, you will often replace "Tidak" with "Ngak", "Gak" or "Tak".

For instance:
Aku gak mau keluar = I don't want to go out

→ When giving a negative order, you should use "Jangan" at the beginning of the sentence.

For instance:
Jangan bilang itu! = Don't say that!

→ When talking about your experiences, your wishes or your tastes, it is better to avoid using a strict negation. The words "Belum" ("Not yet") and "Kurang" (Less) can replace "Tidak" or "Bukan" to form more polite sentences.

For instance:
Instead of "Aku tidak suka makanan Jepang" ("I don't like Japanese food"), say: "Aku kurang suka makanan Jepang" (literally, "I less like Indonesian food").

Instead of "Aku tidak mau nikah" ("I don't want to marry"), say: "Aku belum mau nikah" ("I don't want to marry yet").

To be or not to be?
"To be" is the most common English verb, yet its Indonesian translation, "adalah", is rarely used. It might be confusing for beginners, but the rules are actually quite simple.

→ Generally speaking, "to be" is not needed (unless you want to sound formal). This is particularly true when it is used to describe something/someone or to give characteristics.

For instance:
I am a man = Aku cowok (literally, "I man").
He is fat = Dia gemuk (literally, "He fat").

→ You can use "adalah" to make a statement that two things are equivalent.

For instance:
"Rusia adalah negara terbesar di dunia" = "Russia is the largest country on earth"

→ Another use of "Adalah" is to say that something or someone is part of a group/structure.

For instance:
"Dia adalah pengawai pemerintah" = "He is a government employee".

Indicating presence
To say "There is" or "There are", you should use the popular word "Ada" (also: "Tidak ada" = "There is not"). It is placed at the beginning of sentence such as:
"Tidak ada rokok lagi di toko" = "There are no more cigarettes at the store"
"Ada siapa di rumah kamu?" = "Who is at your house?" (literally, "There is who at your house?")

In informal conversations, "Ada" can also mean "to be present". For instance: "Dia ada di rumah" = "He is at home".

8 comments to '' 10 Basic Indonesian Grammar Rules You Should Know "

  1. "Saya sudah mandi" = "I just ate" (literally, "I just eat").
    Should it not be makan instead of mandi (take a bath)? :)

    1. Haha yes, it's a mistake... Thank you, I just corrected it...

    2. Hi! Great blog with some great comments! Just wanted to share that "I just did X" is best used with the "Aku/Gw/Saya baru saja X..." in CJI. Of course, "sudah" (or pernah, telah, etc, depending on the context) do work fine there! But when people hear "Aku baru saja makan..", I want them to know that is a perfective action, marked similarly with "sudah", except "baru saja" gives the intonation that the act was JUST being completed. Thank you!

  2. Hey really thanks for this good explanation، i appreciate that
    I just moved to Indonesia three months ago and now I started learning Bahasa since month ago, and it really seems a pretty challenging for me to remember the words and their meanings..
    I hope I can speak it after two months ;)

  3. "Aku kurang suka makanan Jepang" (literally, "I less like Indonesian food").
    Japanese instead of Indonesian..��
    Very useful and good explanation brother, appreciate it.
    Thanks a lot ��

  4. Thanks so much! I'm studying Indonesian and this honestly taught me more than my Indonesian teachers ever have haha.

  5. I've only been using Duolingo to study Indonesian and this has helped me so much! Thank you!

  6. as a native Indonesian speaker, this is really a good explanation, good job!