Fluency in a language is not only about vocabulary and grammar but also about how clearly and naturally you express yourself. This involves mastering pronunciation features such as stress, intonation, vowels, consonants, and the way sounds connect in speech. One important feature that makes English sound smooth and natural is Assimilation. In this guide, IDP will explain what assimilation is, the main types, and how to practice it to improve your English communication skills.
1. What is Assimilation
Assimilation is a common linguistic phenomenon that happens when one sound changes to become more similar to a neighboring sound. This change makes pronunciation easier and smoother, especially in fast and connected speech.
According to Oxford (2008), assimilation occurs when two sounds in close contact share similarities in place or manner of articulation. The degree of assimilation often depends on speed and speaking style. Both vowels and consonants can be affected, but research (Bert, 1993) shows that consonants are more likely to undergo assimilation than vowels.
Examples of assimilation in English:
Ten boys → /tem bɔɪz/ instead of /ten bɔɪz/ because /n/ becomes /m/ before /b/.
Good night → /gʊg naɪt/ instead of /gʊd naɪt/ because /d/ is influenced by /n/.
Did you → /dɪdʒuː/ instead of /dɪd juː/ because /d/ and /j/ merge into /dʒ/.
Assimilation is a natural feature of connected speech. For IELTS candidates, recognizing and applying assimilation is essential for both Listening and Speaking.
2. Types of Assimilation in English
According to Celce-Murcia (2002), assimilation in continuous speech can be divided into three main types:
Progressive Assimilation
The following sound changes to match the preceding sound.
Examples:
Get them → /get təm/
Read these → /riːd diːz/
Open → /ˈəʊpm/ instead of /ˈəʊpən/
Regressive Assimilation
The preceding sound changes under the influence of the following sound.
Examples:
Bank → /bæŋk/ instead of /bænk/
Input → /imput/ instead of /input/
Handbag → /hæmbag/ instead of /hændbag/
Common rules:
/t/, /d/, /n/ become /p/, /b/, /m/ before bilabial sounds: ten men → /tem mæn/
/t/ → /k/, /d/ → /g/ before /k/ or /g/: good concert → /gʊg kənˈsɜːt/
/s/ → /ʃ/ before /ʃ/: this shiny → /ðɪʃ ʃaɪni/
Coalescent Assimilation
Two neighboring sounds blend to create a new one.
Examples:
This year → /ðɪʃ jɪə/
Did you → /dɪdʒuː/
Has your → /hæʒɔː/
3. Assimilation in IELTS Speaking
Pronunciation counts for 25 percent of your IELTS Speaking score. To achieve a high band score, you need more than accurate individual sounds—you must also show features of connected speech. Using assimilation naturally helps you:
Improve fluency and coherence by speaking smoothly.
Sound more natural and less robotic, making a stronger impression on the examiner.
4. Assimilation in IELTS Listening
Assimilation also plays an important role in listening comprehension. Native speakers use it constantly, and if you are not familiar with it, you may miss words.
Benefits of mastering assimilation in Listening:
Recognize how native speakers actually pronounce words in fast speech.
Follow the main idea without being confused by sound changes.
Keep up with fast conversations where sounds blend together.
5. How to Practice Assimilation
For Speaking:
Listen and imitate: Copy native speakers from movies, news, or interviews. Pay attention to sound changes.
Practice common phrases: e.g. good morning → /gʊb mɔːrnɪŋ/, would you → /wʊdʒuː/.
Record yourself: Identify where you can apply assimilation to sound more natural.
For Listening:
Active listening: Focus not only on meaning but also on how sounds change in connected speech.
Learn basic rules: Predict how sounds might blend.
Use IPA: Compare the original form with the assimilated form.
Shadowing: Repeat exactly what you hear, including speed and rhythm.
6. Key Vocabulary for Assimilation
Connected speech – natural flow of speech where words link together
Bilabial sounds – sounds made with both lips (/m/, /b/, /p/)
Velar sounds – sounds produced at the back of the mouth (/k/, /g/, /ŋ/)
Sound blending – merging of two sounds into one
Phonetic change – adjustment in sound due to neighboring sounds
7. Apply Assimilation to Boost Your IELTS Performance
Assimilation is a natural part of English speech and a key factor for success in IELTS. By mastering it, you will not only improve your listening comprehension but also make your speaking sound more fluent and closer to native-like speech. Combine assimilation with linking and intonation practice to gain confidence in both the exam and real-life communication.
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