Listen carefully to these word endings. Do they sound the same?

Works. Runs. Watches.

Works ends with an /s/ sound.
Runs ends with a /z/ sound.
Watches ends with an extra syllable — pronounced /ɪz/.

Now listen to more examples. Each word ends in S, but the pronunciation changes. As you listen, try to discover the pattern.

Claps.

Hugs. Rises.

Packs. Dreams. Fixes. Washes. Calls. Changes.

Jumps. Girls’ lunches.

The Rule

There are three possible pronunciations for final S: /s/, /z/, and /ɪz/.

1. Voiceless sounds → /s/

The sounds F, T, K, and P are called voiceless sounds.

Voiceless means there is no vibration in your throat.

Try this:
Put your fingers gently on your throat and say these sounds:

F… T… K… P…

You should feel no vibration.

Now say:
Clap. Pack. Laugh.

Still no vibration at the end.

When a word ends in one of these voiceless sounds, the added S is also voiceless.
So it is pronounced /s/.

Example:
Claps. Packs. Laughs.

2. Voiced sounds → /z/

All other ending sounds (except the special group we’ll mention next) are voiced sounds.

Voiced means your vocal cords vibrate.

Put your fingers on your throat again and say:

B… D… G… L… M… N… V…

You should feel a vibration.

Now say:
Rub. Call. Dream.

You feel vibration at the end.

When we add S to words that end in a voiced sound, the S is also voiced.
So it is pronounced /z/.

Example:
Rubs. Calls. Dreams. Hugs.

3. Special endings → /ɪz/

If a word ends in:

S, SH, CH, J, Z, or a soft G sound

we cannot add just an /s/ or /z/ sound because it would be too difficult to pronounce.

So we add an extra syllable:

/ɪz/

Example:
Watches. Washes. Changes. Rises.

This rule applies to:

Third person singular verbs

Plural nouns

Possessives

Practice

Repeat the sentences and focus carefully on the final sound: /s/, /z/, or /ɪz/. (Pause the audio if necessary.)

1. The dog sleeps by the door.

2. Maria enjoys long walks in the morning.

3. He says the movie amazes everyone.

4. The teacher explains difficult concepts clearly.

5. It surprises me when she finishes so quickly.

6. Water drips from the ceiling during storms.

7. He camps in places where he carries only the basics.

8. That surprises me — not at all.