Pronunciation · Minimal pairs · low functional load
/θ/ vs /s/: think vs sink
In short
The dental /θ/ and the sharp /s/ separate think/sink, thick/sick and mouth/mouse. Research ranks this a low-functional-load contrast (it rarely blocks understanding), but it is one of the most NOTICED features of a non-native accent. This contrast carries a LOW functional load, it separates few word pairs, so while the substitution is noticeable, it rarely blocks understanding. Treat it as polish, not priority.
How to hear (and make) the difference
The tongue tip must be visibly between your teeth for /θ/; check in a mirror. /s/ keeps it hidden behind the teeth. Slow, exaggerated practice rewires the habit fastest.
Most challenging for French, Japanese, Mandarin, Vietnamese, Turkish speakers.
8 minimal pairs with audio
- thinkθɪŋksinksɪŋk
- thickθɪksicksɪk
- thingθɪŋsingsɪŋ
- mouthmaʊθmousemaʊs
- pathpɑːθpasspɑːs
- thumbθʌmsumsʌm
- worthwɜːθworsewɜːs
- faithfeɪθfacefeɪs
Test your ear
Listening drill
/θ/ vs /s/: think vs sink
The tongue tip must be visibly between your teeth for /θ/; check in a mirror. /s/ keeps it hidden behind the teeth. Slow, exaggerated practice rewires the habit fastest.
The contrast in sentences
I think it's broken.
I sink it's broken.
He looked thick.
He looked sick.
Keep exploring
Frequently asked questions
What is the difference between think and sink?
think /θɪŋk/ uses the /θ/ sound while sink /sɪŋk/ uses /s/. The tongue tip must be visibly between your teeth for /θ/; check in a mirror. /s/ keeps it hidden behind the teeth. Slow, exaggerated practice rewires the habit fastest.
Which learners find the /θ/ vs /s/ contrast hardest?
It is most challenging for French, Japanese, Mandarin, Vietnamese, Turkish speakers, whose first languages don't separate these two sounds.