How to pronounce -s endings
Plurals, third-person verbs, and possessives all end in -s, but the ending has three sounds: s in "cats", z in "dogs", and a separate syllable "iz" in "buses". The choice depends on the last sound of the base word, and getting it right makes plurals and present-tense verbs clearer to listeners.
How to make the sound
- 1
Step 1: Find the last sound
Say the base word and check whether the last sound is voiced (a hum in your throat) or voiceless.
- 2
Step 2: Add s or z
Voiceless: add a quiet s. Voiced or vowel: keep the voice going and add z. In both cases the word keeps the same number of syllables.
- 3
Step 3: Add "iz" after hissing sounds
After s, z, sh, ch, or j sounds, add a weak vowel plus z: "bus-iz", "watch-iz". This is the only case that adds a syllable.
Example words
Sounds like s (after voiceless sounds: p, t, k, f, th)
- cats
- books
- stops
- laughs
- months
- hits
- maps
- works
Sounds like z (after voiced sounds and vowels)
- dogs
- words
- plays
- runs
- cars
- ideas
- sees
- loves
Sounds like iz (after s, z, sh, ch, j sounds)
- buses
- watches
- wishes
- judges
- faces
- boxes
- sizes
- catches
Common mistakes
- Using an s sound after a voiced consonant, so "dogs" sounds like "docks".
- Forgetting the extra syllable after hissing sounds ("watch-iz", "bus-iz").
- Dropping the ending altogether, which turns plurals and third-person verbs into singular forms.
Read a sentence and check it
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Read one of these aloud, then stop: The cats and dogs watch the buses. She works, plays, and catches the trains. Two months of wishes and boxes of books.
What Speakeroo listens for
These are the pronunciation patterns from Speakeroo’s speech feature catalog that this target tends to expose. The check above reports the ones it hears.
- Final -s ending unclearUse the correct /s/, /z/ or /ɪz/ ending and keep it audible.
- /s/ and /z/ confusedContrast voiceless airflow for /s/ with vocal-cord vibration for /z/.
- Final consonant devoicedKeep the vocal folds vibrating through voiced endings such as /b/, /d/, /g/ and /z/.
Questions
When is the -s ending pronounced z?
The rule matches the -ed rule. After a voiceless sound the ending is s; after a voiced sound or a vowel it is z; after a hissing sound (s, z, sh, ch, j) it becomes a separate syllable "iz".
Does the -s ending add a syllable?
Only the "iz" ending adds a syllable. "Buses" and "watches" have two syllables; "cats" and "dogs" have one, the same as "cat" and "dog".
Does the rule apply to possessives and verbs too?
Yes. The same rule covers plurals (dogs), third-person verbs (she runs), and possessives (the dog’s bowl).
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