IPA phoneme /ð/

In English, both in Received Pronunciation and in General American, the IPA phonetic symbol /ð/ corresponds to the initial consonant sound in words like "the", and "that" and the middle one in "mother" and "gather".

/ð/ is a voiced consonant; its unvoiced counterpart is IPA phoneme /θ/. Both phonemes are consistently spelled "th". See Decoding exercises: "th".

Common words
With initial /ð/:
 * Grammar words: than - that - the - their - them - then - there - these - they - this - those - though - thus

/ð/ in mid-position:
 * Grammar words: although - another - either - neither - other - rather - together - whether - within /wɪðˈɪn, wɪθˈɪn/ - without /wɪˈðaʊt, wɪθˈaʊt/
 * Content words: bother - brother - clothing - father - farther - feather - further - gather - leather - mother - Netherlands - northern - rhythm - southern /ˈsʌðərn/ - weather

With final /ð/:
 * Grammar word: with /wɪð/ or /wɪθ/
 * Content words: breathe - smooth

Less common words

 * /ð/ in mid-position : heathen, heather, worthy
 * With final /ð/: bathe, booth /buːð, buːθ/, clothe, loathe, soothe, teethe

Irregular plurals
Some words ending in /θ/ have a plural ending in /ðz/
 * baths - mouths - paths - youths

Anticipated pronunciation difficulties depending on L1
Preconceived ideas and other interferences from L1 obviously interfere in many cases with how students perceive - and pronounce - sounds/words in English. The following section aims to point out some of the most typical difficulties teachers and students may encounter regarding pronunciation.

Spanish
The main difficulty is the difference between /ð/ and /d/, that is, they may have difficulty distinguishing between "they" and "day". In Spanish both sounds are allophones. This means that to the Spanish ear [aˈðjos], and [aˈdjos] are heard as the same word, even if only [aˈðjos] is the natural pronunciation of "adiós".

Since in Spanish [d] always follows [n], a sentence such as "can they go?" may be uttered as.

Spain
Many Spanish speakers from Spain don't distinguish clearly between /ð/ and /θ/ and when they see "th" tend to pronounce it /θ/, a sound which corresponds to the letter "z" in Spanish. They even replace the [ð] sound of standard Spanish by [θ]. For example, the name of the satirical website La Verdaz is a phonetic rendering of "La Verdad" in a regional accent from Spain.