The English language has 24 consonant sounds and 20 vowel sounds. They do not match up neatly in a one-to-one relationship with the 26 letters of the English alphabet; rather, the 26 letters are mere clues as to which of the 44 sounds in English to use.

Native Thai speakers have difficulty pronouncing English, because the Thai language lacks some of the sounds in English. Young students will pick up on correct pronunciation on their own as long as they’re given correct examples that exaggerate the difficult sounds. Thai teachers, however, may have been practicing the sounds incorrectly for a long time, so they may need both proper examples and an explicit explanation of how the sound is physically produced.

Before getting into specific tips for teaching each of the difficult sounds, it helps to understand the basics about consonants. 1) They can be made in different parts of the mouth. 2) Air can move in different ways: stopped then released, flowing through the nose, hissing/buzzing through, or flowing freely through the mouth. 3) Finally, a consonant is either voiced or voiceless.

Voicing
Understanding the concept of voiced and voiceless consonants will be a big help to Thai learners. A consonant is voiced if your vocal cords vibrate as you make the consonant sound; otherwise it is voiceless. Try singing “da da da da”. Then try singing “ta ta ta ta”. Which one is easier to keep your singing voice going the whole time? If you answered “da da da”, that’s correct, because the /d/ sound is voiced. The /t/ sound is voiceless, so you have to stop your singing voice each time to pronounce it. Another way to demonstrate voicing is have students hold the front of their neck as they make the sounds. They should only feel strong vibrations for voiced consonants.

Trouble Sounds for Thai learners of English

Sound (IPA)	Examples	Teaching Tips
/v/	of, November	/v/ is similar to /f/ as in “fox”, which the Thai language has. The lower lip touches the upper teeth. The only difference is that /v/ is voiced and /f/ is voiceless. Tell Thai learners to make the /f/ sound, and then add the buzzing sound to it (voicing)
/z/	zebra, is, birds	/z/ is similar to /s/ as in “sun”, which the Thai language has. The tongue is just a little behind the teeth and air hisses through. The only difference is that /z/ is voiced and /s/ is voiceless. Tell Thai learners to make the /s/ sound, and then add the buzzing sound to it (voicing)
/θ/	thank, bath	Thai has nothing like /θ/. The tongue needs to touch the upper teeth and air hisses between the teeth and tongue. When demonstrating this, you can exaggerate sticking the tongue out. /θ/ is voiceless, whereas /ð/ is voiced. This distinction, however, is not critical for beginning learners, because if they accidentally make the wrong sound of the pair it won’t cause confusion as to which word they are saying.
/ð/	father, other, that	Thai has nothing like /ð/. The tongue needs to touch the upper teeth and air buzzes between the teeth and tongue. When demonstrating this, you can exaggerate sticking the tongue out. /ð/ is voiced, whereas /θ/ is voiceless. This distinction, however, is not critical for beginning learners, because if they accidentally make the wrong sound of the pair it won’t cause confusion as to which word they are saying.
/ʃ/	she, wash	The tip of the tongue is a little ways behind the teeth, and air hisses out continuously. Thai does not have /ʃ/, but it does have /tʃ/ as in “cheese”. Tell students to make the /tʃ/ sound (“ch”), but then hold it out.
/ʒ/	Asia, treasure	This sound does not occur frequently in English, so you may want to omit teaching it except for advanced learners. This is the same as /ʃ/ as in “she”, but it is voiced. Once you get students to make /ʃ/ (“sh”), tell them to make it buzz, and check by feeling their necks with their hands.
/r/	read, car	Thais roll their Rs. Getting them to produce the English “r” might be tricky, but if they don’t quite get it, at least their words can still be understood. Tell students that “r” is like the sound of L, but draw the tongue back a little further in the mouth
final sounds	bus, back vs. bag, etc.	When a consonant is at the end of a syllable, Thais will systematically reduce the 24 English consonants to one of the following based on which sound is produced in the same place: p, t, k, m, n, ng, y, w. If the sound you’re working on is one that they have in Thai, point this out to them and then exaggerate its presence at the end of the word. If the sound is foreign to Thai, be sure to practice it in the beginning of syllables before practicing it in syllable-final position.

For more information about the sounds of English, see the Phonetics page.