Lesson: Pronunciation of /s/ in Plurals and 3rd Person Singular (Simple Present)
1) Brief foundation: Voiced vs. Voiceless sounds
Voiceless sounds: vocal cords do not vibrate
Examples: /p t k f θ s/
Voiced sounds: vocal cords vibrate
Examples: /b d g v ð z m n ŋ l r j w/ and all vowels
Quick test: put your fingers on your throat and say /s/ → no vibration (voiceless).
Say /z/ → vibration (voiced).
Mini-exercise
Mark V (voiced) or VL (voiceless):
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/f/ ___
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/b/ ___
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/t/ ___
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/m/ ___
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/s/ ___
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/z/ ___
2) The plural and 3rd person -s / -es: the three pronunciations
English spelling uses -s / -es, but pronunciation depends on the final sound of the base word, not the letter.
Rule A — /s/ (voiceless)
Use /s/ after voiceless sounds (except /s ʃ tʃ/).
Sounds: /p t k f θ/
Examples
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cap → caps /kæps/
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book → books /bʊks/
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laugh → laughs /læfs/
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month → months /mʌnθs/
3rd person
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stop → stops /stɒps/
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work → works /wɜːks/
Connected speech
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She works fast. → /ʃiː wɜːks fɑːst/
Rule B — /z/ (voiced)
Use /z/ after voiced sounds (vowels and voiced consonants).
Sounds: vowels, /b d g v ð m n ŋ l r j w/
Examples
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dog → dogs /dɒɡz/
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pen → pens /penz/
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day → days /deɪz/
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car → cars /kɑːz/
3rd person
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live → lives /lɪvz/
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run → runs /rʌnz/
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play → plays /pleɪz/
Connected speech
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He plays every day. → /hi pleɪz evri deɪ/
Rule C — /ɪz/ (extra syllable)
Use /ɪz/ after sibilant sounds.
Sounds: /s z ʃ ʒ tʃ dʒ/
Examples
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bus → buses /ˈbʌsɪz/
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watch → watches /ˈwɒtʃɪz/
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quiz → quizzes /ˈkwɪzɪz/
3rd person
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miss → misses /ˈmɪsɪz/
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watch → watches /ˈwɒtʃɪz/
Connected speech
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She watches TV. → /ʃi ˈwɒtʃɪz ˌtiːˈviː/
3) Common learner errors (important)
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❌ Pronouncing everything as /s/
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❌ Adding a vowel where it doesn’t exist (dogs ≠ /ˈdɒɡɪs/)
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✔ Decide by the final sound, not spelling
4) Practice — Plurals
A) Choose the correct pronunciation: /s/, /z/, or /ɪz/
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cats
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beds
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phones
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watches
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laughs
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rooms
B) Say them in connected speech
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Two cats sleep here.
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The phones are new.
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Those watches are expensive.
5) Practice — 3rd person singular
A) Choose the correct pronunciation
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She works
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He lives
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She misses
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He plays
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It stops
B) Read aloud (natural, connected speech)
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He lives near us.
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She works on Fridays.
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He misses his friends.
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She plays tennis on Sundays.
6) Final drill (contrast)
Say each pair clearly:
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cap /kæp/ → caps /kæps/
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dog /dɒɡ/ → dogs /dɒɡz/
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bus /bʌs/ → buses /ˈbʌsɪz/
Mastery check: if you can feel vibration for /z/ and no vibration for /s/, you’re doing it right.
Pronunciation of YES, IS and WAS:
yes
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Canonical pronunciation: /jes/ → final /s/ (voiceless)
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In fast, connected speech, it may sound partially voiced, but it does not become /z/.
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After a voiced sound, you may hear slight carry-over voicing, but phonemically it stays /s/.
Examples:
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Yes. → /jes/
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Yes, I know. → /jes aɪ nəʊ/ (the /s/ may sound softer, but not /z/)
✔ So: yes = /s/, not /z/
is
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Always ends in /z/ in normal speech.
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Spelling -s, but pronunciation is /z/ because it’s a weak grammatical word and fully voiced.
Examples:
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He is here. → /hiː z hɪə/
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This is good. → /ðɪs ɪz ɡʊd/
In fast speech:
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What is it? → /wɒts ɪt/ (linking and reduction, but underlying /z/)
✔ is = /z/
was
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Always ends in /z/ in standard modern English.
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The final consonant is voiced.
Examples:
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It was good. → /ɪt wɒz ɡʊd/
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She was there. → /ʃiː wəz ðeə/ (weak form)
✔ was = /z/
Why they differ
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yes is a lexical word with inherent /s/.
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is / was are function words and follow voicing assimilation + historical voicing.
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Plural/3rd-person -s varies by final sound of the stem.
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These words are not plural/3rd-person endings; their final sound is lexical, not grammatical.
Quick summary
| Word | Final sound | Varies by context? |
|---|---|---|
| yes | /s/ | No (only phonetic shading) |
| is | /z/ | No |
| was | /z/ | No |