How to Practice the TH Sound in English: A Complete Guide

Why is the th sound so hard?

The th sound in English is rare. Of the roughly 7,000 languages spoken today, only a small handful use a dental fricative like this, and most of the world's biggest languages do not. Spanish, French, German, Russian, Mandarin, Japanese, Korean, Arabic and Hindi all lack it, which means the majority of English learners are attempting a mouth position they have never made before in their lives. The University of Iowa's Sounds of Speech project maps exactly this articulation, showing how rare a true dental fricative is across the world's major languages.

That is the whole problem in one sentence: you are not bad at the th sound, you have simply never trained the muscles for it. Your tongue has spent decades making the nearest available substitute, usually an s, t, d or f, and it will keep doing that until you deliberately override it.

The good news is that the th sound is mechanically simple. It is one of the easiest English sounds to describe and to produce once you know the position, because it does not require any complex movement or airflow control. The difficulty is not the sound itself, it is unlearning the habit your mouth has already built.

The two th sounds you actually need

Before you practice anything, you need to know that English has two different th sounds, and they are spelled identically. The first is voiced, which means your vocal cords vibrate while you make it. You can feel this by putting two fingers on your throat and saying the word "this", "that", "them" or "mother". You should feel a buzz. In Tutoro, a spoken placement conversation hears you say these words once and uses them to work out which sounds you are substituting, so the practice that follows targets your actual mistake rather than a generic one.

The second is voiceless, with no vibration at all. Say "think", "thank", "three" or "bath" with your fingers on your throat. Nothing buzzes. Both sounds use the exact same tongue and teeth position; the only difference is whether your vocal cords are switched on.

This distinction matters because the two sounds appear in different words and changing one for the other can change the meaning. "Bath" and "bathe" are different words, as are "teeth" and "teethe", or "cloth" and "clothe". You do not need to memorise spelling rules to start, but you do need to be able to produce both versions on demand.

Tongue placement: the one skill that changes everything

Every th sound starts from the same physical position, and getting it right once will fix more of your pronunciation than a month of listening practice. Here is the exact sequence.

First, open your mouth slightly and relax your jaw. Second, push the tip of your tongue forward so it sits lightly between your upper and lower front teeth. The contact should be gentle, not clamped, and only the very tip should protrude, roughly the first few millimetres. Third, blow air out through the small gap between your tongue tip and your upper teeth.

That airflow is the entire sound. For the voiceless th in "think", just let the air pass without using your voice. For the voiced th in "this", switch your vocal cords on while the air passes. If your tongue is too far back, you will get an s or a t. If it is too far forward or your jaw is too tense, you will get a lispy, exaggerated sound that is just as wrong in the other direction.

A mirror is your best tool here. Stand in front of one and slowly say "think" while watching your mouth. You should be able to see the tip of your tongue flash between your teeth. If you cannot see it, your tongue is not far enough forward, and you are almost certainly making an s or a t instead.

A 5-minute daily drill for the th sound

Consistency beats intensity for any pronunciation habit, and five focused minutes a day will outperform an hour once a week. Here is a drill you can run every morning that covers both versions of the sound and builds the muscle memory you need.

Start with one minute of isolated sounds. Alternate slowly between the voiceless th and the voiced th, holding each for a full second: thhh, thhh, thhh. Keep your fingers on your throat so you can feel the vibration switch on and off.

Next, spend a minute on single words. Move through a list that mixes both types: think, this, three, that, thank, them, throw, though. Say each word slowly and exaggerate the th, holding the tongue position a beat longer than feels natural.

Then spend two minutes on short phrases and sentences. Use real sentences like "I think this is the right thing" or "Three of them thanked me". The goal here is to keep the th correct when your mouth is also producing other sounds around it, which is much harder than saying the word in isolation.

Finish with one minute of free speaking on any topic, where you simply try to notice every th as it comes up. This is where the habit transfers into real speech. If you want that final minute scored rather than guessed at, an AI English tutor can listen to you speak and mark each th word as good, fair or poor as you say it, which turns a blind drill into something you can actually measure.

Minimal pairs that force you to hear the difference

Most learners who mispronounce the th sound also cannot hear the difference between th and its substitutes. If you say "free" when you mean "three", the first problem is not your mouth, it is your ear. You have to be able to hear a sound before you can reliably produce it.

Minimal pairs are pairs of words that differ by exactly one sound, and they are the fastest way to train that ear. Here are the pairs that matter most for the th sound, grouped by the mistake you are probably making.

For the s substitution, drill: think and sink, thumb and sum, mouth and mouse, thing and sing, tenth and tense. For the f substitution: three and free, thin and fin, thought and fought, death and deaf. For the t and d substitution, which many speakers of Romance and Asian languages make: tin and thin, tree and three, dare and there, dough and though.

Record yourself saying each pair, then listen back and mark which word you actually produced. The recording is essential, because your brain will tell you that you said "three" while your mouth said "free", and you will not notice without hearing it played back.

How to know when you get it right

Pronunciation practice has a unique problem that grammar and vocabulary practice do not: you cannot hear your own mistakes reliably. When you read a sentence, you know whether you understood it. When you say the word "three", your brain has already decided it is correct, regardless of what your mouth actually did. Research on self-monitoring in speech production shows that speakers consistently fail to detect their own articulation errors in real time, which is why external feedback matters so much.

This is why feedback is the single biggest factor in whether pronunciation practice works. A learner who gets no feedback can practise the wrong sound for months and reinforce it. A learner who gets immediate feedback on each attempt improves far faster, because the correction lands at the moment the mistake is made.

There are three realistic sources of that feedback. A human teacher or a patient native-speaking friend is the gold standard, but most people do not have one available for daily five-minute drills. Recording yourself and comparing against a reference audio works, but it is slow and requires a decent ear. The third option is a tool that listens and scores you live.

This is where immediate, word-by-word feedback changes the game. When you practise a sentence aloud, a tool that marks each th word as good, fair or poor the moment you say it gives you exactly the correction loop you need, without waiting for a lesson. That is the kind of feedback built into English speaking practice with AI, where the tutor listens to your reply and scores your pronunciation per word, so a weak th gets flagged the instant it happens rather than three days later.

Tutoro runs pronunciation as part of a live conversation rather than a separate exercise. Its AI tutors speak to you, listen to your replies, and score every word as good, fair or poor the moment you say it, so a th that keeps coming out as an s is caught in the sentence where it happens. The word-by-word scoring is the lead feature here, and it pairs with a tutor who adapts the next exercise to the sounds you got wrong.

It suits learners who want feedback without booking a lesson; it does not suit anyone who wants to study pronunciation in silence rather than by speaking.

How to practice the th sound in English when you keep saying s or d

If you have drilled the tongue position and you still catch yourself saying "sink" for "think" or "dare" for "there", the problem is almost certainly your tongue retracting under time pressure. The correct position is physically easy; the hard part is holding it while your mouth rushes to the next sound.

The fix is to slow down to an almost absurd degree. Take the word "three" and stretch it: thhh-rrr-eee. Your tongue has to stay between your teeth for the entire first second of that word. If you speed up and the th collapses into an s or t, go slower again. Speed is the enemy of a new mouth position, and you should only add it back once the slow version is flawless.

One more trick helps with the voiced th specifically. Because the voiced version requires your vocal cords to buzz, you can force yourself into the right position by starting with a long, exaggerated hum. Say "mmmmmm" and then push your tongue forward into the th position without stopping the buzz. You will land on a voiced th almost automatically, and this connection is why the word "mother" has a voiced th while "think" does not.

Finally, accept that the th sound will be wrong in fast, casual speech long after it is right in careful practice. That is normal and it is not a failure. The goal is to make the correct version your default over weeks and months, not to be perfect on day three. Every learner who has ever fixed this sound went through a stage of saying it right slowly and wrong quickly, and the ones who succeeded are simply the ones who kept drilling through that stage.