/s/ · alveolar fricative Spanish s looks like the Mandarin s but differs in two ways: the tongue tip sits further forward, flat against the ridge rather than in a groove, and final s must be pronounced. The commonest error for Mandarin speakers is dropping final s — los amigos becomes lo amigo — and that final s is the only mark of plural and of «you».
Four steps to /s/
Confirm the gesture, then learn where it changes, then put it in words.
Flatten the tongue, no groove
The Mandarin s has a grooved tongue tip; Spanish s is flatter and wider (laminal). The difference is subtle but the Spanish s sounds «thinner» and closer to the upper teeth.
Pronounce final s
The loudest accent marker. casas has two syllables but both s are pronounced. Drop the final one and plurals and verb endings collapse.
In Latin America z / ce / ci are also s
zapato, cerveza, cine: θ in Spain, s in Latin America. That is seseo, not an error — both are standard. The corpus here is Peninsular, so those words carry θ and live on the θ page.
Do not let s drift towards sh
Spanish s has no retroflex colour; do not curl the tip back. In a mirror the tip should be visible just behind the upper teeth.
Spelling: s has two sources
One is s written as s; the other is that in Latin American accents z / ce / ci are also read [s].
The same in Spain and in Latin America: [s] at the start, in the middle and at the end.
Spain reads [θ]. Both are standard accents; this site's corpus is peninsular, so these words appear on the θ page.
As above. Note that c + a/o/u is [k] (casa) and is not covered by this rule.
Which one are you
The three most common readings.
los amigos comes out as «lo amigo»
The commonest one: the final s is gone. In Spanish it marks plural and person, so dropping it is a grammar error, not just an accent.
My s sounds a bit like sh
The tip is curled. Mandarin has separate sh and s; Spanish has only one s — tongue flat and forward.
Should I say s or θ
Depends on the accent: Peninsular z/ce/ci is θ, Latin American is s. Both are correct as long as you are consistent.
Word list
20 words grouped by where the sound sits in the word. Click a word to hear it. These are recorded as separate words, not cut out of the sentences above — a word cut from a sentence carries its neighbours' transitions and always sounds muddier. All three groups use the same speaker, so what changes between them is position, not voice.
Word-initial8
Word-medial8
Word-final4
Corpus and acoustic measurements
Click any word in a sentence to play from that word. The pale band over the waveform marks the measured boundary of the target word.
Per-token data
Every number below is measured directly from the audio, not hand-annotated.
| Token | Accent | Sex | Target | Target word | /s/ duration | F0 | Pitch range | HNR |
|---|
Where these numbers come from
12 synthetic sentences from two Peninsular voices; phoneme boundaries from MMS_FA.
Corpus: 12 Spanish sentences whose target words contain s, with the target word never sentence-initial or sentence-final (those positions are distorted by pauses and sentence stress).
Boundaries: MMS_FA forced alignment; word and phoneme boundaries come from the same pass. The target phoneme is looked up in the word as declared by the page, never taken blindly from the onset.
Target duration: the column is the length of the target phoneme itself, not the whole word. The «target word» column is the word.
All 12 target words contain s, covering onset (sol), medial (casa) and coda positions. The page reports duration. ★ One thing we did not do: the spectral centre of gravity (>4 kHz) could separate s from θ, but every item here is Peninsular and every target is s — there is nothing to compare against, so the number would carry no information.
What this page does not do: no paired differences (there is no pair to compare), and no verdict on whether you pronounce it correctly — the durations describe native speech, not a scoring standard.