TH is the most famous English sound that many languages do not have. So learners swap in the closest sound they know: “tink”, “fink”, “sink”, “dis”, “zis”. The real sound is easier than it seems, and fixing it improves many words at once.
The two TH sounds
| Sound | Symbol | Examples | Vocal cords |
|---|---|---|---|
| Voiceless | /θ/ | think, three, thanks, month, health | Do not vibrate |
| Voiced | /ð/ | this, that, the, they, mother, with | Vibrate |
Put your hand on your throat. With the voiced sound you feel a buzz; with the voiceless one, only air.
How to make the sound
- Place the tip of your tongue lightly between your upper and lower teeth. You do not need to stick it far out.
- Push air gently through the gap between your tongue and your upper teeth.
- For voiceless /θ/, only air. For voiced /ð/, add your voice, like a very soft “d”.
A simple test: say “sss” and then slide your tongue forward until it touches your teeth, without stopping the air. The sound that comes out is /θ/.
The most common substitutions
| You say | It sounds like | Intended word |
|---|---|---|
| ”tink” or “sink” | tink, sink | think |
| ”tree” | tree | three |
| ”sank you” | sank | thank you |
| ”dis” or “zis” | dis, zis | this |
| ”den” | den | then |
Speakers of Spanish and Portuguese tend to use “t” and “d”; speakers of French, German and many Asian languages often use “s” and “z”. Some learners who picked up English from music use “f”.
Minimal pairs to practice
Read them aloud and feel the difference:
- think / sink / tink
- three / tree / free
- thank / tank
- they / day
- then / den
- mouth / mouse
Sentences to practice
- “I think there are three of them.”
- “Thank you for this, that was thoughtful.”
- “They’re together in the theater.”
- “My mother and father both think so.”
Start slowly, exaggerating the tongue position. Then speed up until it sounds natural.
Where to hear TH at real speed
TH shows up constantly in words like “the”, “this” and “that”, so any TV show works as practice. The trick is to listen closely to those small words, which almost disappear in fast speech. In Telidioma you can replay the line where a word appeared and hear each word pronounced on its own. To understand why small words vanish in speech, read how to improve your English listening.
Frequently asked questions
How do I know if TH is voiced or voiceless?
There is no perfect rule, but small, very common function words (the, this, that, they, there, then, with) are usually voiced, and content words (think, three, thanks, health, month) are usually voiceless.
Does replacing TH with “d” or “s” cause misunderstandings?
Context usually helps, but some words turn into others: think and sink, three and tree, then and den. Getting the sound right avoids those mix-ups.
Do native speakers always pronounce TH?
No. In some accents, such as parts of London and some American dialects, TH often becomes “f” or “d”. Still, the standard taught and expected is TH with the tongue between the teeth.