As in the other cases in which consonants are arranged in pairs (see table 2), /θ/ and /ð/ share manner and place of articulation and differ in voicing (/θ/ is voiceless and /ð/ is voiced). This means that the only difference between them is that /ð/ is produced with vocal fold vibration and /θ/ without. The phoneme /θ/ is very easy for speakers of Peninsular Spanish because it’s the sound included in words such as azul or zapato, but it’s absent in the Spanish spoken in Latin America. The voiced version of this sound, /ð/, doesn’t have such a clear equivalent and tends to cause more trouble. Many Spanish speakers produce it just as a plosive /d/, which is not. Learning to do it well, however, is quite a simple task.
Another problem is that, since both /θ/ and /ð/ are spelled as th, it’s difficult to say for sure when to use one or the other. Although there are no hard and fast rules about that, some very useful guidelines can be given.
Let’s start by listening to these sentences:
Spelling: th (thief, breath)
The phoneme /θ/ is very well known to speakers of Peninsular Spanish. It’s the same used in words like zapato, zona, cima o cenar.
Listen to this contrast:
For those who do not count /θ/ among the sounds of their mother tongue -basically, Latin American speakers-, the instructions on how to do it are quite straightforward. Put your tongue behind your upper teeth or, in a more careful pronunciation, slightly protruding between them. Then let the air pass and you’ll hear the hissing fricative noise that constitutes the /θ/.
And here is an example of the /θ/ sound produced by a native speaker of English (none other than the writer Julian Barnes reading from his novel Arthur & George):
Spelling: th, the (that, breathe)
The phoneme /ð/ doesn’t exist in Spanish as such, but it isn’t a difficult sound. It’s the voiced counterpart of /θ/, so it is produced in the same place an manner, with the tongue behind the upper teeth or, in a more careful pronunciation, between the upper and the bottom teeth.
As in similar cases, our first attempt at this sound will involve two steps. First, say the voiceless version of the phoneme, /θ/. Second, add the voicing. Like this:
Here’s a good example of the /ð/ sound, in the voice of actor Jeremy Irons.
I said that the phoneme /ð/ doesn’t exist as such in Spanish. However, as Spanish speakers, we actually do produce the sound /ð/ inadvertently in some contexts, that is, as an allophone. This basically occurs in two situations: 1. When we pronounce the letter d between vowels (todo, ido, miedo, etc.); 2. When it is final (libertad, amad). Let’s have a look at it.
Listen and repeat:
Each example has two letters d. If you listen carefully to yourself and, even more important, if you feel what’s happening in your mouth, you’ll notice that, in each case, the first d (dedo, de madera) is different from the second d (dedo, de madera).
In Spanish, when the letter d comes at the beginning of a word it is a plosive sound and the tip of the tongue is located a bit higher (against the place where the teeth are inserted into the alveoles). On the other hand, when d comes between vowels it is fricative and the tongue is placed lower (against the bottom part of your upper teeth or between the two sets of teeth, that is, in an interdental position).
And why is all this so important? Because this intervocalic sound you do hundreds of times a day in Spanish is the one you have to produce in English to say words such as they, those, that, although, etc. What is more, you do it also when the letter d comes at the end of words and it’s followed by a pause.
So, the conclusion is that, if you can do it in Spanish, you can do it in English too. Remember: it’s only a matter of lowering your tongue a little bit and let the air pass gently.
Listen to the difference:
Now, in this recording, you can here the difference between /ð/, /θ/ and /d/.
And where do they go?
One of the problems we face with /ð/ and /θ/ is that they share spelling (always the diagraph th), so it’s difficult to say which phoneme goes where. There are, however, some useful guidelines:
- At the beginning of words, th is usually pronounced as /ð/ when it’s a function word (determiner, conjunction, pronoun, etc.). E.g. that, those, them, though. Lexical words (nouns, verbs, adjectives and adverbs) beginning with th, instead, are normally pronounce with /θ/. E.g. think, thorn, thumb, thorough.
- At the end of words, /ð/is very likely to occur in verbs, very often -but not always- followed by e. E.g. loathe, bathe, breathe, writhe. In nouns, on the other hand, final th is normally realized as /θ/. E.g. truth, flesh, cloth, stealth. This gives rise to interesting pairs: mouth (noun, /maʊθ/) – mouth (verb /maʊð/).
- In some cases, th is pronounced just as /t/: Thames, Thomas, thyme, Thailand.