The -s Ending (/s/, /z/, /ɪz/)

Intermediate · Tricky Endings

The "-s" ending on plurals, possessives, and third-person verbs also has three pronunciations, following the same voiced/voiceless logic as "-ed". Again, only one case adds an extra syllable.

Getting this right makes plurals and present-tense verbs sound clean and correct.

The 3 pronunciations

after voiceless → /s/ (cats). after voiced → /z/ (dogs). after s/z/sh/ch/j → /ɪz/ +syllable (buses).

Rules & examples

1. /ɪz/ (extra syllable) after s, z, sh, ch, j sounds.

   The only case that adds a syllable.

   • buses, boxes, watches, wishes, changes
2. /s/ after a voiceless sound (p, t, k, f).

   A clean hiss, no extra vowel.

   • cats, books, cups, laughs
3. /z/ after a voiced sound (vowels, b, d, g, l, n, r...).

   A buzz, no extra vowel.

   • dogs, pens, cars, plays, goes

Minimal pairs

• cats (/s/) / dogs (/z/) — voiceless vs voiced ending
• books (/s/) / buses (/ɪz/) — no extra syllable vs extra syllable

Tips to remember

• Same logic as -ed: voiceless → /s/, voiced → /z/, and hissing endings → /ɪz/.
• Only s/z/sh/ch/j endings add the extra "iz" syllable (buses, watches).