English as an Additional Language/The "Th" Sound

The letters "TH" are used to represent the voiced and the voiceless dental fricatives (/ð/ and /θ/, respectively). These phonemes are two of, while common in the English language, but are among the rarest phonemes globally. That is, in most languages (probably yours, if you are not an English speaker) it does not exist, and speakers of those languages find it hard to pronounce them and often replace them with /s/ and /z/ or /t/ and /d/. Whilst pronouncing "TH" as one of these will not stop you from being understood by an English speaker, you may want to be able to do it properly, particularly when speaking to a non-native speaker of English, who may have more difficulty making the distinction between words such as think and sink, which sound identical when spoken by someone who can't make the "TH" sounds. This page is a step-by-step guide to pronouncing those sounds.

How to pronounce /θ/

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1) Stick your tongue between your teeth (don't worry if it looks silly), leaving a small gap between your tongue and your top teeth
2) Push the air out, keeping that gap between your tongue and your teeth tight

Practice it with this sentence: I think the therapist thanked me for thawing out his three throbbing thighs in a thief's thatched theatre.

3) When you are confident doing the sound with your teeth sticking out, try moving your teeth back into your mouth a bit each time you try it, until you can say the sound with the tip of your tongue just behind your teeth (or just beneath them if you are struggling.

How to pronounce /ð/

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1) Do the above two steps
2) But when you are pushing the air out, make sure your vocal cords are vibrating. I.e., push the air out whilst humming

Practice it with this sentence: These and those are the only ones whose rhythm from Netherlands makes this brother fathom the weather, though these make rather smoother rhythm.