by Ana Paula Biazon Rocha

In many English Language Teaching (ELT) coursebooks and online resources, a common pronunciation point is the so-called ‘TH sound’, a lay term used to describe the interdental fricatives /θ/ as in ‘teeth’ /tiːθ/ and /ð/ as in ‘teethe’ /tiːð/. A wide range of activities, such as games, quizzes, tongue twisters, songs, and more, are used to help second language (L2) learners produce these sounds more accurately. These two sounds are usually considered key features of the English sound system, often contrasted with other languages. As Hall and Hastings (2017, p. 83) mention, ‘very few languages in the world have either of these sounds.’ However, I wonder if, in the name of ‘teaching pronunciation’, many teachers overemphasise the relevance of the ‘TH sound’, which, in fact, should be ‘sounds’ (plural), and their impact on intelligibility1. For example, the Lingua Franca Core (Jenkins, 2000) explicitly states that these sounds do not affect intelligibility, particularly in international communication between non-native speakers of English2. So, why do many teachers and students continue to view the /θ/ and /ð/ sounds as crucial to pronunciation? Should teachers stop teaching them? And if so, what should they focus on instead? Do learners have any say in this?

1. Why do many English learners find it challenging to pronounce the /θ/ and /ð/ sounds?

As mentioned above, these two sounds are absent from the sound inventory of most languages. Consequently, English learners often lack L1 references for them and must learn how to articulate them from scratch. Teachers usually ask students to place their tongue between their teeth and exhale to produce the voiceless sound /θ/, or refrain from exhaling to create the voiced sound /ð/. The use of minimal pairs, which are rare in this case, can also help learners recognise and practice the distinction:

  • thigh (n.) /θaɪ/ – thy (det.) /ðaɪ/
  • teeth (n.) /tiːθ/ – teethe (v.) /tiːð/
  • ether (n.) /ˈiːθər/ – either (adv.) /ˈaɪðər, ˈiːðər/
  • loath (n.) /ləʊθ/ – loathe (v.) /ləʊð/ 
  • mouth (n.) /maʊθ/ – mouth (v.) /maʊð/

Due to the lack of L1 references, many learners usually substitute similar sounds from their native language when trying to pronounce /θ/ and /ð/. For instance, the verb ‘think’ /θɪŋk/ might be pronounced as ‘sink’ /sɪŋk/, ‘zink’ /zɪŋk/, ‘fink’ /fɪŋk/, or even ‘tink’ /tɪŋk/. This is not a deliberate error but rather an effort to make sense of two unfamiliar sounds.

Differences in the articulation of these sounds can also be found in different varieties of English:

  • Hall and Hastings (2017) comment that in some dialects of English, the /θ/ and /ð/ sounds do not exist: ‘when people say, ‘He da man’ (‘He’s the man’, which means ‘he’s really cool’), they have replaced the rare /ð/ phoneme with the very common /d/ phoneme, which is much more common in world languages’ (p. 83). 
  • Hudson (2021, p. 82) explains that ‘in most areas of England, especially in large cities, some people don’t pronounce dental fricative /θ/, instead they say /f/’, such as in ‘fing’ (thing), ‘free’ (three), or ‘baf’ (bath). This is called ‘th’ fronting. 
  • Hancock (2024, p. 85) highlights that many Irish speakers pronounce the /θ/ and /ð/ sounds as /t/ and /d/, so minimal pairs such as ‘thin-tin’ and ‘then-den’ have no distinction. He also points out that ‘for many West Indian speakers, such pairs [thin-tin, then-den] are actually homophones’. 

2. Should teachers and learners spend class time on the /θ/ and /ð/ sounds?

One might claim that saying ‘free’ instead of ‘three’ can cause breaches in communication:

A: I’d like ‘free’ (three) coffees to go, please.
B: Free? No, you have to pay for them.
A: No, I said ‘free’ (three)…1, 2, ‘free’ (three)!
B: Huh? (looking puzzled)

No, nobody is arguing against it. However, according to Levis (2018, p. 15), the /θ/ and /ð/ sounds are only likely to be confused in a small number of rare words, and if learners struggle with either sound, they are more likely to replace /θ/ with other voiceless sounds such as /s, t, f/ rather than confusing it with the voiced interdental fricative. In other words, they will probably say ‘free’ meaning ‘three’ /θriː/ (voiceless sound) instead of ‘three’ /ðriː/ (voiced sound).

Another thing to consider is that a clear distinction between the /θ/ and /ð/ sounds is based on native speakers’ ears. To put it simply, many native speakers of English can clearly distinguish and produce the two sounds, or not produce them at all, as noted before. In contrast, our learners are not native speakers of English, so is it necessary to make them produce the /θ/ and /ð/ sounds impeccably?

Based on Jenkins (2000), in contexts where English is used as a lingua franca, with non-native speakers using the language as a medium for communication, difficulties with the /θ/ and /ð/ sounds generally do not affect intelligibility. In other words, substituting these sounds with alternatives from a speaker’s L1, such as /s, z, t, d/, is unlikely to lead to misunderstandings in such interactions. This is because the focus in lingua franca communication tends to be on functional comprehension rather than sticking to native-like pronunciation norms. Other pronunciation features, such as the aspiration of plosives /p, t, k/ at the beginning of words (e.g., pat, town, cold), are more likely to impact intelligibility. When these sounds are produced with weak aspiration, they may be misheard as their voiced counterparts /b, d, g/, as in bat, down, gold (Walker, Low & Setter, 2021). For an overview of the Lingua Franca Core (Jenkins, 2000), a framework to help teachers prioritize pronunciation features for intelligibility, please check Walker, Low and Setter (2021, p. 15) or Walker and Archer (2024, p. 92-94).

3. Why might many teachers overemphasise the relevance of the /θ/ and /ð/ sounds?

As constantly reiterated in our PronSIG blog, research on pronunciation instruction shows that many teachers feel unsure about teaching pronunciation and lack adequate training, skills and confidence (Derwing & Munro, 2015; Walker, Low & Setter, 2021). For this reason, it seems to be easier to hold on to common pronunciation topics that we often see in ELT materials and resources than exploring the ‘unknown’, for instance, the Lingua Franca Core, or suprasegmentals such as stress, pausing, intonation, and linking sounds.

In this regard, Levis (2018) explains that when evaluating our ability to understand a speaker with a foreign accent, we tend to exaggerate the impact of the accent and focus on mistakes we can easily identify, often giving those errors more weight in determining intelligibility than they actually deserve. Thus, ‘segmental errors, especially obvious ones like substitutions for /θ/, are noticeable and we can name them’ (p. 29). Similarly, if I am an English teacher and need to add some pronunciation work to my lessons, besides everything else that I also need to juggle (e.g., classroom management, syllabus and time constraints, students’ interests and needs, assessment, etc.), I might go with the obvious, within my comfort zone, within the safe place, with the ones I know how to name, and that’s when the /θ/ and /ð/ sounds come in handy. We can do some minimal pairs practice, we can have fun with tongue twisters (e.g. The thirty-three thieves thought that they thrilled the throne throughout Thursday), we can watch a funny video (e.g., German Coastguard We are Sinking/ What are you Thinking About), we can play a game, and the pronunciation work is done, one less thing to tick off my list. Likewise, when giving feedback on pronunciation, if there is not much to point out about pronunciation, I can always make a comment about the ‘TH sounds’, even though it might not be that relevant, can’t I? However, the real question seems to be: ‘Am I really teaching pronunciation for intelligible communication?’

4. OK, so are we ditching the /θ/ and /ð/ sounds, then?

Not exactly! They are part of the English sound system and should still be taught, but perhaps with a bit less focus than other pronunciation features. In fact, we can change how we approach these sounds. As reiterated by Hancock (2024, p. 84), the /θ/ and /ð/ sounds can be treated as ‘optional pronunciation points’ in terms of production. Students can work on articulating them, but if they end up using /s, z, f, t, d/ instead, there is no need to correct them right away. However, when teaching pronunciation for listening, it is important to raise students’ awareness of the different ways both native and non-native speakers pronounce these sounds.

Finally, we also need to consider the context and the specific needs of our learners. Pronunciation should be taught based on those needs, and if /θ/ and /ð/ happen to be relevant, then we teach them! What I believe many teachers should avoid doing is relying solely on familiar materials and resources from their comfort zone, or using the ‘TH sounds’ as a way to mask any fear, uncertainty, or lack of confidence in teaching pronunciation.

Last but not least, please check Hancock (2024, p. 84-87) and Smolder (2012, p. 16-17), for examples of practical and useful activities to teach the /θ/ and /ð/ sounds. 

For more on pronunciation instruction, please check our previous blog posts. Don’t forget to leave your comments below and follow PronSIG on social media.

1In order to clarify the meaning of concepts used in this post such as intelligibility, English as a Lingua Franca, suprasegmentals, among others, please refer to this previous blog post.

2In this post, the terms native speakers and non-native speakers were used to facilitate understanding. For a more in-depth discussion on the meaning and use of these terms, please refer to this previous blog post.

References

Derwing, T. & Munro, M. (2015). Pronunciation fundamentals: Evidence-based perspectives for L2 teaching and research. John Benjamins.

Hall, C. & Hastings, C. (2017). Phonetics, Phonology and Pronunciation for the Language Classroom. Palgrave. Macmillan Education.

Hancock, M. (2024) PronPack: The Minimal Pair Collection. Accent-Friendly Pronunciation Teaching. Hancock McDonald ELT.

Hudson, J. (2021). The Sounds of English. A Practical Course in Standard (GB) British English Pronunciation. Pronunciation Studio.

Jenkins, J. (2000). The Phonology of English as an International Language. Oxford University Press.

Levis, J. (2018). Intelligibility, Oral Communication, and the Teaching of Pronunciation. Cambridge University Press.

Smolder, C. M. (2012). Be understood! A pronunciation resource for every classroom. Cambridge University Press. 

Walker, R. & Archer, G. (2024). Teaching English Pronunciation for a Global World. Oxford University Press.

Walker, R., Low, E. & Setter, J. (2021). English pronunciation for a global world [PDF]. Oxford University Press. www.oup.com/elt/expert