Professional language training for aviation careers
Call us for a free telephone consultation: +852 8179 9295

Listen to Aviation English Radio

Prepare for your ICAO test, learn aviation theory, hear student experiences and get hints and tips to improve your English.


pronunciation-logo Pronunciation -

In this section of Learning Zone we focus on pronunciation in Aviation English. Pronunciation is a fundamental part of language learning and "must be given priority"

In this article by Aviation English Asia Ltd you are going to learn about the pronunciation of 's' as the final sound of verbs in third person and plural nouns.  The ending 's' is pronounced /s/ after a voiceless sound, pronounced /z/ after a voiced sound and  pronounced /ɪz / or /əz/ after a sibilant sound.  But what does this mean?  Read on to find out.

Third person verbs

The correct use and pronunciation of verbs in third person is classified as a Basic Structure in the AEROSTA Framework and ICAO Document 9835.  It is a area of language in which pronunciation overlaps with structure, and it is most likely that it is used when describing facts, eg scientific principles, habits and timetables.  Pronunciation errors such as these are cumulative, and in combination with other errors can cause communication difficulties.

Plural nouns 

The same rules of pronunciation of 's' also apply to plural nouns. But be aware that there are a number of exceptions, most frequent of all "debris" which is a French word and actually has a silent 's'.

Debris on the runway

Basic concepts of pronunciation

The pronunciation of final 's' depends on the last sound of the word.  If you read our introductory article Terms and concepts used in English pronunciation you will be aware of the difference between voiced and unvoiced consonants, as well as sibilant sounds.  As a quick recap,

  • a voiced consonant is one that that requires effort from the vocal chords (a vibration or humming sound).  For example, if you put two fingers on your throat and make the W sound you will feel a vibration.  That vibration means that it is a voiced sound.
  • an unvoiced sound is where there is no vibration in the throat and instead the sound comes from the mouth area. If you pronounce the letter P you will notice how it comes from your mouth not the throat.
  • a sibilant sound is produced by forcing air out toward your teeth. Is is characterized by a long hissing sound (sssss like a snalke), or a buzzing sound (zzzzz like a bee) at the end of words

The rules

The pronunciation of the final 's' in verbs in third person and plural words will depend on the final consonant sound (not the letter - letters in English often have a different pronunciation) before that 's'.  These are the rules for pronunciation, although there are a number of exceptions.

Sibilant: reduces, increases /sɪz / or /səz /, air-bridges /dʒɪz / or /dʒəz /, pushes /shɪz / or /shəz /
Voiced: crabs /bz/ -- birds /dz/ -- gloves /vz/, flows
Voiceless: helps /ps/ - rectracts /ts/ - looks /ks/ - cliffs /fs/ graphs /fs/

ICAO Aviation English Pronunciation of S

1. The /ɪz/ sound (or sometimes /əz/ sound) 

If the last consonant sound of the word is a sibilant sound (a hissing or buzzing sound), the final 's' is pronounced as /ɪz/. This /ɪz/ sound is pronounced like an extra syllable. (e.g. the word masses has two syllables)

If the sound has a J sound (/dʒ/ like the letter J at the beginning of the word juliet or /ʒ/ like the S in Asia), then the final 's' is also pronounced as /ɪz/.

Examples of words ending in the /ɪz/ sound:

CE: races (eg pronounced like "race-iz"), reverses, buses
S: pauses, rises
X: fixes, taxes, hoaxes
Z:, freezes, prizes, 
SS: kisses, misses, passes, bosses
CH: sandwiches, teaches
SH: wishes, pushes, crashes
GE: gauges, garages, changes, ages,

Remember: after verbs ending in -sh, -ch, -ss and -x, we add the -es to the end of the verb (in third person) and the pronunciation is /iz/ as an extra syllable.

2. The /s/ sound

If the last consonant of the word is unvoiced, then the 's' is pronounced as /s/. It does not require an extra syllable

NOTE: The consonants c, s, sh, ch and x are voiceless though they use the sibilants ending seen above.

Examples of words ending in the /s/ sound:

P: cups, stops, sleeps
T: hats, students, hits, writes
K: cooks, books, drinks, walks
KT: retracts, instruments (pronounced retracTs, not retracs)
F: cliffs, beliefs, laughs, graphs, (the -gh and -ph here are pronounced like a F)
TH: myths, tablecloths, months (voiceless th)

3. The /z/ sound

If the last letter of the words ends in a voiced consonant (or sound), then the S is pronounced like a /z/ (without creating another syllable). 

We also use this ending when the word ends in a vowel sound (e.g. bees, flies etc.)

Examples of words ending in the /z/ sound:

B: crabs, rubs
O: flows
E: trees
D: retards, reads, words, rides, ends
G: tugs, bags, 
L: deals, calls, falls, aerofoils 
M: climbs, dreams
N: fans, drains, runs, pens
NG: wings, belongs, sings
R: wears, cures
V: gloves, wives, shelves, drives
Y: plays, relays,
THE: clothes, bathes, breathes


Listen to the sentences in the audio below and identify the endings of the words. 


What to do next For more information about Aviation English Asia’s courses please visit or call +852 81799295. 
If you haven't already please join the Aviation English mailing list for special offers and details of courses in your area.

 Aviation English Pronunciation

English learning advice from Aviation English Asia Ltd

Pronunciation in air to ground communications is very different to pronunciation when talking to other people face to face.  As a learner of Aviation English it is important to realise that there is English, and there is phraseology in radiotelephony - with few overlaps between.  Pronunciation is a frequent area of failure in ICAO English Language Proficiency tests and one that is often neglected because it is difficult for a learner to identify that they have a specific problem.  Aviation English Asia Ltd teachers are qualified and experienced in diagnosing a wide range of language issues, and when feedback is given it is often done using very specific meta-language used by teachers.  In this article we introduce some of the terms and concepts used to identify areas of pronunciation.  Of course, pronunciation errors are cumulative and you may have more than one difficulty. We will briefly define the components of pronunciation from smallest unit of sound to those in a sentence. 


A phoneme is a unit of sound. Phonemes are expressed as phonetic symbols in the IPA (International Phonetic Alphabet). Some letters have one phoneme, others have two such as the diphthong 'ire' as in fire (AI - uh). Sometimes a phoneme may be a combination of two letters such as 'ch' in 'checklist', or 'fl' in 'flight'. 


There are twenty-six letters in the English alphabet. Some letters are pronounced differently depending on the letters preceding and following them. For example, 'c' can be pronounced like a hard /k/ in retract or as an /s/ in the verb 'practice'. Letters are made up of consonants and vowels. Consonants can be voiced or voiceless depending on the sound (or phoneme). The difference between voiced and voiceless is explained below.


Consonants are the sounds that interrupt vowel sounds. Consonants are combined with vowels to form a syllable. They include:

b, c, d, f, g, h, j, k, l, m, n, p, q, r, s, t, v, w, x, z

Consonants can be voiced or unvoiced.


Vowels are open sounds caused with the vibration of vocal sounds, but without obstruction. Consonants interrupt vowels to form syllables. They include:

a, e, i, o, u and sometimes (at the end of a word) y 

All vowels are voiced as they are produced using the vocal chords.


A voiced consonant is a consonant that is produced with the help of the vocal chords. You can identify if a consonant is voiced by placing your fingers to your throat. If the consonant is voiced, you will feel a vibration. Understanding whether a consonant is voiced or unvoiced will have a massive impact on your ability to improve your pronunciation.

Voiced Consonant Sounds

b, d, g, j, l, m, n, r, v, w


A voiceless consonant is a consonant that is produced without the help of the vocal chords. Place your fingers on your throat when speaking an unvoiced consonant and you will only feel a rush of air through your throat. With some you can also feel the air escaping from your mouth.

Unvoiced Consonants

c, f, h, k, q, s, t, x

Minimal Pairs

Minimal pairs are pairs of words that differ in only one sound. For example: 'ship' and 'sheep' differ in only in the vowel sound. Minimal pairs are used to practice slight differences in sound.  Aviation English Asia Ltd teachers will identify the minimal pairs which are most relevant to you.


A syllable is formed by a consonant sound combining with a vowel sound. Words can have one or more syllables, and sometimes diphthongs which can often be confused with syllables. To test how many syllables a word has, put your hand under your chin and speak the word. Every time your jaw moves indicates another syllable.

Syllable Stress

Syllable stress refers to the syllable that receives the main stress in each word. Some two syllable words are stressed on the first syllable: pilot, checklist - other two syllable words are stressed on the second syllable: retract, return. There are a number of different word syllable stress patterns in English.  Sometimes it's useful to learn the rules, but for many learners it's easier to just learn the correct pronunciation of the word.

Tonic Stress

Tonic stress refers to which words are stressed in a sentence. We can divide these into content words and function words.  Usually, content words are spoken slower (it is a mistake to say that content words are spoken louder) and glide over function words.

Content Words

Content words are words that convey meaning and include nouns, main verbs, adjectives, adverbs and negatives. Content words are the focus of a sentence. Stress these content words to provide the rhythm of English by gliding, or skipping over the function words.  At least one word in a sentence carries the main meaning of the sentence and is called the tonic.

Function Words

Function words are words that required for the grammar, but that provide little or no content. They include auxiliary verbs, pronouns, prepositions, articles, etc. 

Stress-Timed Language

When speaking about English we say that the language is stress-timed. In other words, the rhythm of English is created by words stress, rather than syllable stress as in syllabic languages.

Word Groups

Word groups are groups of words that are commonly grouped together and before or after which we pause. Word groups are often indicated by commas such as in complex or compound sentences.

Rising Intonation

Rising intonation occurs when the voice goes up in pitch. For example, we use rising intonation at the end of yes / no questions. We also use rising intonation with lists, separating each item with a short rise in the voice, before a final, falling intonation for the last item in a list. For example in the instruction:

Cessna 345, contact Bay departure one two seven point zero.

'3', '4', '5', '1', '2', '7' and 'point' would rise in intonation, while 'zero' would fall. 

Falling Intonation

Falling intonation is used with information sentences and, in general, at the end of statements.


Reductions refers to the common practice of combing a number of words into a short unit. This generally occurs with function words. A few common reduction examples are: gonna -> going to / wanna -> want to.  It is generally regarded as bad practice to use reductions in radio communication.


Contractions are used when shortening the helping verb. In this way, two words such as 'is not' become one 'isn't' with only one vowel. 

What to do next

Aviation English Asia Ltd offer pronunciation activities in every course, and also in Supplementary Classes each weekend. For further details email This email address is being protected from spambots. You need JavaScript enabled to view it. or call +852 81799295.



Hong Kong

Aviation English Asia has been offering part time and full time courses in Hong Kong since 2009.

All courses are available in Hong Kong. Check the schedule above for details.


Aviation English Asia has been offering part time courses in Vietnam since 2014.

All courses are available in Vietnam - typically every 8 weeks, or by special arrangement.


ICAO Aviation English, English for Aircraft Maintenance Engineers, Technicians and Mechanics, and English for Flight Attendants are available in Taipei, Tainan and Kaosiung.


Member of the Aviation English Organisation


matf Pronunciation -


Workplace English Campaign

Protected by COPYSCAPE