The TH Sounds (/θ/ and /ð/)

Intermediate · Consonant Sounds

The "th" is the sound most languages don't have, so it is the classic giveaway of a non-native accent. There are actually two of them: a voiceless /θ/ (think, bath) and a voiced /ð/ (this, mother). Both are made the same way — the difference is only the throat "buzz".

The secret is the tongue position: the tip of your tongue lightly touches the back of your top teeth (or peeks just between the teeth) and air flows over it. Many learners replace it with /t/, /d/, /s/, /z/, or /f/ — say "tink/dis/sink" and it changes the word.

How to make it

Tongue tip lightly on/between the teeth, blow air. /θ/ = no buzz (think). /ð/ = with buzz (this).

Rules & examples

1. Voiceless /θ/ — air only, no vibration.

   A soft hiss over the tongue and teeth.

   • think, thank, three, bath, mouth, healthy
2. Voiced /ð/ — same position, but add the throat buzz.

   Common in small grammar words (the, this, that, they).

   • this, that, the, mother, brother, weather
3. Feel your tongue touch your teeth.

   If your tongue stays behind your teeth, you are probably making /t/, /d/, /s/ or /z/ instead.

   • Put your tongue tip on your top teeth and blow: "th-th-th".

Minimal pairs

• think / sink — /θ/ vs /s/ — tongue on teeth, not behind
• thin / tin — /θ/ vs /t/
• they / day — /ð/ vs /d/
• breathe / breed — /ð/ vs /d/
• three / free — /θ/ vs /f/

Tips to remember

• Start by letting your tongue peek visibly between your teeth — you can hide it more once the sound is reliable.
• Practise the voiced /ð/ on the tiny words you use constantly: the, this, that, they, them.

Common mistakes

• ✗ "I tink dis is good." → ✓ "I think this is good." — Replacing /θ/ /ð/ with /t/ /d/ is the most common th-error; the tongue must touch the teeth.