Indonesian, also known as Bahasa Indonesian, is the official language of Indonesia. It is spoken by roughly 200 million people in countries across the globe, including Indonesia, the Netherlands, the Philippines, Saudi Arabia, Singapore, and the United States. It is also recognized as a working language in East Timor. In this post we will share features of Indonesian speech and language development to help SLPs provide culturally appropriate care and accurate assessments for Indonesian-speaking clients, as well as support teachers and literacy specialists in supporting Indonesian-speaking students.
Indonesian is part of the Austronesian language family and is a standardized variety of Malay, another Austronesian language. The Indonesian vocabulary is also greatly influenced by other languages and consists of a large number of loanwords, particularly from Dutch, English, and Arabic. Indonesia has a complex and diverse history, influenced by centuries of trade, the rise and fall of powerful kingdoms, and periods of Portuguese, Dutch, and Japanese colonization. This historical background has significantly shaped the country’s language and culture and Bahasa Indonesia was adopted as the national language to unify the nation after independence in 1945.
Indonesian has far more L2 (second language) speakers than L1 (first language) speakers. This is primarily because Indonesia has over 700 native languages. As a result, many individuals’ L1 is their local language, and their L2 is Indonesian. This type of Indonesian is typically referred to as Standard Indonesian, as it is used in more formal settings such as the media, schools, and workplaces. In informal settings, the Indonesian language often shifts depending on the local language influencing it, resulting in various vernacular varieties of the language.
Interesting Facts About Indonesian Speech and Language Development
- Indonesia is the world’s largest archipelago, consisting of over 17,000 islands, with around 6,000 that are inhabited.
- The country is home to more than 1,300 ethnic groups, each with its own unique customs and traditions.
- Indonesian is in the top 10 most spoken languages in the world! This is largely due to the population of Indonesia being over 273 million people.
- Standard Indonesian is known as a lingua franca or bridge language/common language among ethnic groups in Indonesia due to the large number of native languages throughout the country. As a result, Standard Indonesian is the language used within education, business, media, and other formal communication purposes.
- The Indonesian language is incredibly adaptable and playful—people often shorten words or create slang by reversing syllables, like “ojek” (motorbike taxi) becoming “jeko,” making it a dynamic and evolving part of daily communication, especially among youth.
- The national language, Bahasa Indonesia, is a standardized form of Malay used throughout the country.
- Indonesia’s national motto is “Bhinneka Tunggal Ika,” which translates to “Unity in Diversity” in Old Javanese.
:
Indonesian Speech and Language Development
Indonesian Consonants in Comparison to English
| Indonesian Consonants Not Shared with English | /ʔ/ (glottal stop)¹ |
| Consonants Shared With English | /p/ /b/ /t/ /d/ /k/ /g/ /s/ /ʃ/ /h/ /m/ /n/ /ŋ/ /j/ /l/ /w/ |
| English Consonants Not Shared with Indonesian | /f/ /v/ /z/ /ʒ/ /tʃ/ /dʒ/ /ð/ /θ/ /ɹ/ |
Indonesian Vowels in Comparison to English
| Indonesian Vowels Not Shared with English | None |
| Vowels Shared With English | //a/ /i/ /u/ /e/ /o/ /ə/³ |
| English Vowels Not Shared with Indonesian | /ɚ/ /ɔ/ /ʌ/ /ʊ/ /ɛ/ /I/ /æ/ |
Notes on this Indonesian Phonology
- Indonesian’s glottal stop /ʔ/ is a distinct phoneme, especially word-finally (e.g., ‘bapak → /bapaʔ/)
- Indonesian includes /ŋ/ (ng) natively, unlike English where it cannot start a word.
- The six phonemic vowels in Indonesian (/a, i, u, e, o, ə/) match many, but not all, English vowels; it lacks English’s more complex and reduced vowels .
The Use of Phonotactic Constraints in Indonesian Speakers
Indonesian phonotactics define specific rules about how sounds can be structured in native words. These constraints shape how Indonesian speakers pronounce or adapt English, especially when encountering unfamiliar sound patterns. Recognizing these patterns helps clinicians differentiate between typical language transfer and true speech disorders.
Key Phonotactic Constraints in Indonesian:
- Maximal Syllable Structure: CVC Only
Indonesian syllables follow a strict CVC pattern, with no complex consonant clusters at the beginning or end of native words (journals.linguisticsociety.org). - **Epenthesis to Resolve Clusters**
Loanwords featuring consonant clusters are adapted by inserting a vowel (usually /ə/) to maintain the CVC structure.
Example: “klub” → /kə.lub/ (journals.linguisticsociety.org, slam.lin.ufl.edu). - No Complex Codas
Codas are limited to a single consonant. Final clusters are reduced by deletion or vowel insertion (ijssh.net). - Restricted Onset Clusters
Initial clusters are rare; only a few permissible combinations exist (e.g., /pr/, /tr/, /kr/), and unexpected clusters are simplified (ijssh.net). - Unaspirated Voiceless Plosives
Indonesian lacks aspiration in voiceless stops (e.g., /p/, /t/, /k/), so English initial stops may be produced unaspirated (mdpi.com). - Variable Realization of /v/ and /z/
Voiced fricatives /v/ and /z/ are not native; speakers may substitute them with /f/ or /s/, or vary between voiced and voiceless realizations (mdpi.com).
Implications for English Speakers
- Expect vowel insertion in English words with clusters (“street” → /sə.trit/).
- Final consonants may be omitted or followed by a vowel (“big” → /bigə/).
- Word-initial stops may lack aspiration, sounding softer than in English.
- Non-native fricatives may be replaced or devoiced, affecting voiced–voiceless contrasts.
Indonesian Speech Developmental Norms
| Age of Acquisition | Sounds |
|---|---|
| By ~2;0 years | Children typically have mastered all six vowels (/a, i, u, e, o, ə/) and most consonants, especially stops and nasals.ejournal.iainmadura.ac.id+15atlantis-press.com+15jurnal.uns.ac.id+15 |
| By ~3;0 years | Most children produce diphthongs correctly. |
| By ~4;0 years | Nearly the full consonant inventory is acquired, though fricatives (e.g., /f/) and /r/ may still be emerging; final consonants often show variability, with some realized as [n]. |
Developmental Norms Summary
- Vowels: Complete inventory (/a, i, u, e, o, ə/) typically mastered by age 2.jurnal.fs.umi.ac.id+14atlantis-press.com+14en.wikipedia.org+14
- Diphthongs: Generally acquired by around age 3.atlantis-press.com
- Consonants: Core consonants (stops, nasals, glides) are in place by age 2; fricatives and the trill /r/ solidify around age 4. Final consonant production may vary.
Language Specific Differences Between English and Indonesian
Indonesian and English share some surface similarities, such as a Subject–Verb–Object (SVO) word order, but they differ greatly in grammar features important for speech-language pathologists. Indonesian lacks articles (“a,” “the”) and plural noun marking—context or reduplication signals quantity instead. There’s no verb conjugation for tense or person; tense is expressed with time adverbs or aspect words like sudah (already) or akan (will). Pronouns are gender-neutral, and negation is placed before verbs or nouns (tidak, bukan), with questions formed simply by intonation or using apakah—no sentence inversion or auxiliary “do.” These features affect how Indonesian-language speakers learn and use English, and understanding them helps distinguish language differences from disorders.
| Language Features | Indonesian | English |
|---|---|---|
| Sentence Word Order | SVO, same as English; focus/emphasis may front elements (bahasabule.com, en.wikipedia.org) | SVO |
| Adjectives/Noun Modifiers | Adjectives, possessives, demonstratives follow nouns | Adjectives precede nouns |
| Possessives | Possessor follows noun or uses modifying phrase, e.g., rumah saya (“house my”) | Possessor precedes noun + ’s |
| Possessive Pronouns | Free pronouns like saya, kamu, dia; no separate possessive pronoun category | my, your, his, her, etc. |
| Verb inflection | No conjugation; affixes for voice/aspect (e.g. me- active, di- passive) | Verbs change for tense |
| Pronouns | Multiple pronouns, e.g., formal (Anda) vs. informal (kamu) | Independent pronouns required |
| Pronoun Gender | No gender distinction (dia used for he/she/it) | he, she, it |
| Subjects of Sentences | Often dropped; context clear | Normally expressed |
| Regular Past Tense | No “-ed”; use sudah or time words for past | verb + -ed |
| Irregular Past Tense | No distinction; same as regular past marking | irregular forms (went, saw) |
| Negatives | tidak negates verbs/adjectives; bukan negates nouns | Uses “not” or auxiliary verbs |
| Double Negatives | Rarely used enlivened emphasis possible, not standard | Present in dialects |
| Question formation | Rising intonation or apakah; no inversion | Auxiliary inversion (“Do you…?”) |
| Definite Articles | None | “the” |
| Indefinite Articles | None; context, se-, or classifiers used | “a,” “an” |
| Prepositions | Prepositions similar but limited; spatial/time via relational nouns | in, on, at |
| Present Progressive Verb Form | sedang before verb; no “-ing” | verb + -ing |
| Modal Verbs | No modal verbs; aspect or context expresses modality | can, will, must |
| Copula/“To Be” Verbs | Zero-copula; adalah/itu sometimes used | is, are, am |
| Auxiliary Verbs | No do, have auxiliaries | do, have, be |
| Passive Voice | Passive via di- affix; basic word order changes | “be” + past participle |
| Direct Object Pronouns | Incorporated into verbs (-ku, -mu) | me, him, her |
| Conjunctions | dan (“and”), atau (“or”), tetapi (“but”) | and, but, or |
| Plurals | Reduplication or context; no -s | noun + -s |
Additional Austronesian Languages
This is just one of over ten Austronesian languages that we have documented in the World Language Library. Click below to explore languages spanning the Philippines, Pacific Islands, and Southeast Asia.
| Tagalog/Filipino | Ilocano (Ilocos region, Philippines) | Malay |
| Indonesian | Chamorro (Guam) | Palauan (Micronesia) |
| Māori | Hawaiian | Samoan |
| Chuukese | Marshallese | Pohnpeian |
| Vietnamese |
Sources:
“A Beginner’s Guide to Basic Indonesian Grammar.” IndonesianPod101, 18 Mar. 2021, https://www.indonesianpod101.com/blog/2021/03/18/indonesian-grammar-overview/. (indonesianpod101.com)
Adelina Anum, Ratna Susanti, and Abd. Syakur. “Indonesian Language Acquisition of 0–2-Year-Old Children.” Journal of Tamaddun: Life, vol. 20, no. 1, 2022.
Adnyani, N. L. P. S., & Pastika, I. W. (2016). Phonological development in the early speech of an Indonesian-German bilingual child. Research in Language, 14(3), 329-350.
Andi-Pallawa, B., & Alam, A. F. A. (2013). A comparative analysis between English and Indonesian phonological systems. International Journal of English Language Education, 1(3), 103-129.
Ariefiand, R. “Constructing Questions in Indonesian.” Richariefiandy.Tk, 13 July 2016,
“Bahasa Indonesian.” Asia Society, Accessed 25 Oct. 2023.
Herlina. “Phonological Acquisition of Children of Age 3;4–3;10 Years: Case Study on Razka Salim Mirza.” Atlantis Press Proceedings, vol. IClA‑18, 2015.
“Indonesian language.” Wikipedia, Wikimedia Foundation, accessed June 2025, https://en.wikipedia.org/wiki/Indonesian_language. (en.wikipedia.org)
“Indonesian Language.” Wikipedia, Wikimedia Foundation, 23 Oct. 2023.
“Indonesian Negation: Learn How to Form Negative Sentences.” IndonesianPod101, 10 Aug. 2021, https://www.indonesianpod101.com/blog/2021/08/10/indonesian-negation/. (indonesianpod101.com)
IndonesianPod101. “Indonesian Conjunctions: List of Indonesian Linking Words.” IndonesianPod101.Com Blog, 17 Jan. 2020.
International Journal of Social Science and Humanity. “Final Consonant Clusters Simplification by Indonesian Learners of English.” 2014.
Languages, Voccent. “Introduction to Bahasa Indonesia: Indonesia’s National Language.” Medium, Medium, 5 Aug. 2023.
Susanto, Deri Sis Nanda, et al. “Analyzing the Speech Sound Structures of Indonesian Child Language.” Okara: Jurnal Bahasa dan Sastra, vol. 16, no. 2, Nov. 2022, pp. 301–318.
Syam, Fadilla. “Pronunciation Features of Indonesian‑Accented English.” MDPI Linguistics, 2024.
“Word and syllable constraints in Indonesian adaptation: OT analysis.” Linguistic Society of America, 2015.
Zarbaliyev, Habib. “Phonotactic Features of the Indonesian Language.” Linguistic Researches, 2022.
dergipark.anas.az
Contributors:
A special thanks to Kennedy Beyersdorf with Concordia University- Wisconsin for data compilation and research that went into this article!
