Let's start at the beginning; no prior Thai reading experience is required!

To read Thai, we must understand how an orthographic syllable is constructed. The first thing to note is that we're going to be careful to distinguish between an orthographic—that is, written—syllable and a phonetic syllable. The reason for this will become clear later on. Don't worry about this too much now; just remember to be flexible about your old grammar-school idea of a syllable. So let's start by dissecting a written syllable in Thai.

Syllable Basics

First, let's note that, like English, the Thai alphabet is divided into consonants and vowels. Before continuing this lesson, take a moment to look at the consonants reference page. If it's convenient on your computer, you might want to keep it open in another browser while you read on.

You probably noticed that each consonant has two sounds associated with it: one for when it appears at the beginning of a syllable and one for when it appears at the end of syllable. This provides our first clue to the Anatomy of a Spoken Thai Syllable. We'll be working with the following diagram throughout this lesson.

This diagram represents what you will be thinking about when you actually speak a Thai syllable aloud. In other words, you'll always make the sound of the initial consonant first, then the vowel sound, and end with the final consonant sound. This may seem obvious, but it's important because as we study reading and writing Thai, you'll find that the position of the letters (or graphemes) as you read from left to right sometimes doesn't proceed as you might expect.
We'll soon be plugging consonant graphemes into both of these boxes. Keep your consonant reference chart handy; when a letter appears in the 'Initial' box, we'll look up its sound from the column marked initial, and when it appears in the 'Final' box, we'll look up its sound from the column marked final.

You might have noticed in the consonant chart that a few consonants do not have a syllable-ending sound defined (marked 'n/a' in the chart). They can never appear in the 'Final' box.
The vowel sound can be long (สระเสียงยาว  /saL raL siiangR yaaoM/) or short (สระเสียงสั้น  /saL raL siiangR sanF/), which refers to the relative amount of time that the vowel sound is held. You'll want to get the vowel duration correct to be sure you're understood. Some syllables stop there; they don't have a final consonant sound. This is called an open syllable. I'm sure you can think of some open syllables in English, like we, or all three syllables of patio. In these cases, the 'Final' consonant box in our diagram will be left empty. If the optional final consonant sound is present, then the syllable is called closed. In English, like cat which ends with consonant /t/.

To complete our introduction to the syllable diagram, I'll point out that the overall syllable must be spoken with the correct tone, which is one of the following: low (เสียงเอก  /siiangR aehkL/), mid (เสียงสามัญ  /siiangR saaR manM/), high (เสียงตรี  /siiangR dtreeM/), falling (เสียงโท  /siiangR thohM/), or rising (เสียงจัตวา  /siiangR jatL dtaL waaM/). The proper tone to use is determined by a few different factors, such as the class of the initial consonant, the vowel duration, and the type of final consonant, if any.

For the rest of this article, we'll continue discussing the basic alphabetic composition of the syllable, but please remain aware of the other characteristics of the syllable that must be properly pronounced: the correct vowel duration and tone.

You're now ready to read your first word in Thai. Don't click the speaker icon yet.

กับ    (with; to; for)

Let's see if you can piece it together yourself. Refer to your consonant page to determine the sound for ก when it's an initial consonant. Also look up the sound for บ when it's a final consonant. On the vowels reference page, you'll find the vowel -ั in row 1 of the basic vowel sounds, but I'll help you out: this vowel symbol represents an /-a-/ sound. As you can see, it's written above—and a little bit to the right of—the initial consonant. This chart also tells us that it's a short-duration vowel sound.

Determining the tone is a little more involved, but in case you're curious at this point, the low spoken tone is determined by the fact that ก is a mid-class consonant, and บ is a dead ending. Refer to the tone rules page for more information.

Putting it all together, this syllable (and word) is pronounced /gapL/ (note: In your site control panel, you can configure the system used for displaying romanizations on this page). Now practice saying the word and carefully compare with the audio clip. That was simple! Congratulations on reading your first word in Thai.

Next, we'll look at a syllable without a written vowel. If no vowel symbol appears in the syllable, then the vowel sound /-oh-/ is implied. (This special vowel appears in row 7 of the vowel chart, where it says [inherent].)

กบ     (frog)

I hope you didn't have to refer to the consonant chart because this syllable uses the same initial and final consonants as above. The only difference is the absence of a written vowel. This is pronounced, /gohpL/. Did you get it right?

Vowel Orthography

Earlier, I mentioned that the ordering of the letters in written Thai can be unexpected sometimes. In particular, some vowel characters are written in places that might seem strange to a student familiar only with western languages. Keeping this in mind, now examine the fifteen basic vowel graphemes (symbols). All vowel and diphthong symbols are built up from one or more of these parts. Memorize them, concentrating on differentiating them from the forty-four consonant graphemes. You must be able to distinguish Thai consonants from vowels. It won't be hard, though, because you'll soon realize that they generally don't look like each other at all. Here's an example where the vowel is placed below the inital consonant. Also, there's no final consonant.

งู    (snake)

Did you look up the initial consonant in the consonant chart? Did you find the vowel in row 9 of the vowel chart? The romanization is /nguuM/. As for figuring out the tone: being an open syllable with a long duration vowel, the syllable is live. Since ง is a sonorant (low-class) consonant, the spoken tone is 'mid.'

Perhaps the most startling case is when the vowel is written before the initial consonant. It bears repeating, though: even with a preposed vowel, the syllable is still spoken in the order: initial + vowel + final. Our diagram always shows the order of speaking the sounds.

ไม่    (not; no)

I'm sure this was one of the first words you learned when you studied spoken Thai: /maiF/. Study this case carefully until you're comfortable with the idea of the vowel sound coming after the initial consonant, despite the vowel symbol being written before it. We aren't discussing the tone marks here yet, but in this case, the stroke over the initial consonant is the first of the four tone marks used in Thai. In this case, it gives the syllable a 'falling' spoken tone.
Some vowels combine several 'pieces' which surround the initial consonant, but they still count as a single vowel sound. Here's a more complex case.

เตียง    (bed)

Study this case carefully. The vowel insinuates itself all around the initial consonant and the final consonant is tacked on the end. Notice that this compound vowel symbol incorporates three different symbols which surround the initial consonant on three sides. You can find this vowel in row 14 of the diphthong section of the vowels page. The consonant ย is considered part of the vowel. Later, we'll be introducing the terminology "straddling" to describe how a vowel with a preposed element surrounds the initial consonant. Did you sound out the word yet? You should have gotten something like /dtiiangM/. Final ร with an Implied Vowel

When the consonant ร is used as a final consonant in a syllable with no written vowel, it is usually pronounced /-aawn/.

ศร  /saawnR/   (arrow)

Final Cluster /-รถ/ or /-รท/

A consonant cluster is any grouping of two consonants that are stated together without a written vowel. We'll spend much of the rest of this article discussing consonant clusters which act as the initial consonant in a syllable. But first, we'll introduce a cluster that takes the place of the syllable's final consonant:

ศารท   /saatL/   (harvest time; harvest festival)

Now we've got two letters in the final consonant box. In the clusters /-รถ/ and /-รท/, the ร is silent, so we simply pronounce a final /-t/ sound, and the word is pronounced /saatL/. A two-syllable word that uses this type of cluster is สามารถ . See if you can puzzle out the pronunciation before clicking on the word (or speaker) to see (or hear) the answer.

What if we were to place a consonant cluster in the initial consonant box? Next, we'll begin to examine how to read words that do this.

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Initial Consonant Clusters

We can expand upon the twenty-one initial consonant sounds that are available with simple initial consonants by beginning to consider two consonants appearing together: consonant clusters.¹ In Thai, they're called อักษรควบ  /akL saawnR khuaapF/. We'll be looking at three types of consonant cluster and this is where we'll really begin hewing closely to a native Thai grammatical sensibility. We'll learn to think about words like a Thai!

I. - True Consonant Clusters

We'll start with the simplest type of cluster, the true consonant cluster (อักษรควบแท้  /akL saawnR khuaapF thaaeH/). A cluster is 'true' if both of the consonant sounds are 'blended' or 'melded' together so that, as you speak the overall sound, both letters contribute equally. Examples in English are: quick, which starts with a clustered /kw-/ sound, or price, which starts with /pr-/. If you think about it, you'll realize that, because of physiological constraints on speech, only certain consonants can be combined in this way. Try saying the nonsense word, 'gkow;' unless you're a Klingon, you probably can't, without sounding a vowel between the /g/ and /k/. The /g/ and /k/ sounds won't blend. Here's the first example:

กว่า    ([suffix used for comparisons] than; more; -er)

This sounds like /gwaaL/; you probably know the word already from your conversation studies. Notice how, when you say it, your mouth forms the initial consonant cluster into a single blended sound, which all happens before the vowel sound. This word has no final consonant.

Our approach to understanding syllables reduces the number of rules you must learn. There's one simple rule that's very important, though. Please commit it to memory: In the case of กว่า , this means that we use ก, a mid-class consonant, along with the presence of the ไม้เอก   /maaiH aehkL/ tone mark to determine that the spoken tone must be low.

This is a good chance to point out some orthographic details which apply to all clusters: the tone mark for a cluster, if any, is written over the second consonant in the cluster, as shown in the previous example. Superposed and subposed vowels are also written over the second consonant. And as we'll see next, any preposed vowel element is placed before the entire cluster. This word uses true cluster /คร-/:

ใคร่    (to wish, to desire, or prefer)

Just as we did when there was a single initial consonant instead of an initial consonant cluster, the preposed vowel is placed in front of the whole shebang. Before continuing, study the example words listed under 'Type I - True Clusters' on the Consonant Clusters reference page.

II. - False Consonant Clusters

We've just seen that in true consonant clusters, the two consonants were blended, equally participating in the formation of the syllable-initial sound. Next, we'll examine consonant clusters in which the second consonant is ร and it's completely silent. This type of cluster is called อักษรควบไม่แท้  /akL saawnR khuaapF maiF thaaeH/, or a false consonant cluster. For example:

สร้าง    (to build; construct; create; establish; to cause)

It's pronounced /saangF/. Let's run through the tone calculation for this one. Since we always use the first consonant of the cluster to determine the tone (according to the rule), we note that the first consonant, ส, is a high-class consonant. When the second tone mark, ไม้โท   /maaiH thohM/, is present, as it is here, we know that the syllable must be spoken with a falling tone.

In some cases, the presence of the silent ร influences the pronunciation of the syllable. In Thai, this is called ออกเสียงแปรไปเป็นเสียงตัวอื่น  /aawkL siiangR bpraaeM bpaiM bpenM siiangR dtuaaM euunL/.

ทราบ    ([polite] to know a fact or piece of information)

Here, thanks to the influence of silent ร, ทร is pronounced as /s-/, not /th-/ as you might expect. The correct pronunciation of the word is /saapF/.

Interestingly, this particular consonant cluster can also operate the same way as a final consonant cluster. In the next example, concentrate on the final consonant box and don't worry about the 'non-conforming' cluster in the initial consonant position (we'll be discussing non-conforming clusters below). The important thing to see at this point is that the false consonant cluster ทร is acting as a /-t/ sound, so the following is pronounced /saL mootL/:

สมุทร    (ocean; sea)

Preposed vowels in false consonant clusters are still handled in the same way as discussed above. For more practice, take a look at this one, which uses the false cluster /ซร-/:

ไซร้   ([a particle used at the end of a conditional clause for emphasis or rhetoric effect] certainly)

This word is pronounced /saiH/. Just as we did with true clusters, the preposed vowel is placed in front of the whole cluster, so it's the first grapheme in the syllable. This means that, when reading Thai text—which is all run together, without spaces between the words or syllables—the preposed vowels can help you recognize where syllables start. You can find more examples of false clusters listed under 'Type II' on the Consonant Clusters reference page.

III. - 'Leading Consonant' Clusters

The final type of consonant cluster is a broadly-defined category. We've already looked at true consonant clusters and false consonant clusters. Any remaining cases of two consonants appearing together with the same vowel are called อักษรควบที่ใช้อักษรนำ  /akL saawnR khuaapF theeF chaiH akL saawnR nahmM/, or 'leading consonant' clusters. This remainder bin covers a lot of territory, so we'll break down a few distinct patterns. All are very common in Thai, so you won't want to skip this section.

a. - Tone-shifting 'Leading Consonant' Clusters

A large number of Thai words use an initial consonant cluster in which the first consonant—which must be either ห or อ—is silent. If you've learned about these silent leading consonants before, you probably memorized a rule about how the tone is affected in such syllables. But now we'll see that, with our one simple rule, we actually don't have to introduce anything new to understand these clusters!

หนู     (mouse; mice; rat)

If you haven't started studying the tone rules yet, you can just note that the ห in this cluster is silent, so we get the pronunciation /nuuR/. ห is called หอ นำ  /haawR nahmM/, or "leading H-" in this role.

But read on, and you'll see that figuring the tone becomes simple when we remember our rule: the tone of the syllable is determined by the first consonant in the cluster. In this case, it's the silent ห, a high-class consonant. This means that we get to use the high-class tone rules for a syllable which, from a pronunciation standpoint, starts with the low-class consonant น! The leading ห "provides access" to the rising and low spoken tones, which are normally not available to low-class consonants. In the case of หนู  , the tone is rising because of the long vowel and the open syllable.

"Leading H" (หอ นำ) can appear in a cluster when the second consonant is any one of the low class sonorant consonants { ง, น, ม, ย, ร, ล, ว, ญ, ณ, ฬ }. It's essential to provide this method for changing the tone of these sonorant initial consonants, because unlike all of the other low-class consonants which have a high-class phonetic equivalent consonant, these would otherwise have no way to deliver the rising or low spoken tones.

In addition to หอ นำ, there are four words that use อ in exactly the same way—as a silent, leading consonant that ends up shifting the tone of the syllable. This use is called ออ นำ  /aawM nahmM/. b. - Non-conforming 'Leading Consonant' Clusters

So far, the distinction between orthographic syllables and phonetic syllables that we accentuated earlier has not seemed important. Each written syllable we've studied (except for /saL mootL/, which we glossed over) has signified a single spoken syllable. Now we'll see that certain initial consonant clusters can seem to break this pattern.

If the clustered consonants can't be blended (as in a true consonant cluster) or simplified (as in a false consonant cluster) then how can they be pronounced? We got a clue to the answer when we were looking at the Klingon-language example above. If you force yourself to speak consonants that won't blend, you'll find yourself inserting a hardly-perceptible vowel sound in-between them. This becomes an unwritten -ะ sound (very short /-a/) pronounced as part of the consonant cluster. We'll call such clusters non-conforming, since the two consonants aren't compatible with each other. One Thai teacher suggested thinking of it as "one-quarter of a full vowel." Here's the first example:

สนาม    (field; park; lawn; playground; meadow; yard; turf; grassy field)

Even though we still think of this as a single written syllable, it's pronounced /saL naamR/. The short vowel is encapsulated, or 'nested' fully within the orthographic syllable, a 'sub-syllable,' if you will. The first, immediate benefit of thinking of it this way—as opposed to thinking of /saL/ as a separate, standalone syllable—is that your pronunciation of the overall syllable improves when you try to force the initial consonant cluster into sounding as a unit. Try it both ways; you'll notice a difference. Now you're speaking like a Thai!

A non-conforming initial cluster can appear with an implied vowel:

ถนน    (road; boulevard; avenue; street)

I'm sure you know this word, /thaL nohnR/. It has no written vowels, but now we know how to break it down into an initial cluster which contains a sub-syllable /-a/ and the inherent vowel /-oh-/. The latter connects the initial cluster to the final consonant.

Now consider the tone of the overall syllable. As we've been discussing, we should think of this a single orthographic syllable. What would happen if we instead thought of ถนน  as two independent syllables, /thaL/ and /nohnR/? The tone of the first, having a high-class initial consonant (ถ) and being an open syllable with a short vowel, is low. So far, so good. But now wait, the second 'syllable' (นน) has a low-class initial consonant and a live ending; the tone should be mid!? This way of thinking breaks down.

Now, let's zoom in on just the initial consonant box:

When we realize that the unwritten vowel -ะ is fully encapsulated within the consonant cluster, we can see that the initial consonant that's exposed to the overall orthographic syllable is ถ, a high-class consonant. That sub-syllable that we had to insert to make the cluster pronuncable isn't perceptible enough to cancel the first consonant's effect on the overall syllable (remember the rule?). Now, when we apply the tone rules, we come up with the correct spoken tone for the word, rising⁴. To make sure you've got it, see if you can rephrase it in your own words. Try reading this well-known word: นคร. You'll have to use much of what you've learned so far.

So as we've seen with the other types of consonant clusters, the spoken tone of the overall syllable is still determined by the consonant class of the first consonant in the cluster (ถ, in our example). So remember, keep the clustered consonants together, thinking of the cluster as a unit which contains the sub-syllable /ถะ/ within it.

Let's take a moment to recognize the difference between the implied /-oh-/ vowel that we encountered earlier, and this implied /-a/. The former is a full-fledged vowel which can occupy the light-green triangle in our diagram, connecting an initial consonant to a final consonant. The latter is a sub-syllable sound which exists intra-cluster and makes the pronunciation of the cluster possible. We should be sure to appreciate that they have little in common with each other except that neither is explicitly written.

c. - Preposed Vowels in Non-conforming Clusters

We've seen how important it is to keep the two consonants in a cluster coupled together. But we haven't even discussed what's perhaps one of the most compelling reasons why. We'll now see how doing this seamlessly handles what could otherwise be a confusing situation: using a vowel with a preposed element in a syllable with a non-conforming initial consonant cluster.

Consider the word เฉลียง, which is pronounced /chaL liiangR/. If you try to build syllables in a linear fashion, by scanning the word from left-to-right, you'll find yourself in a jumble. The first character, เ, is a preposed vowel which is part of the overall compound vowel. You'd have to ignore it for now. Next you'd encounter ฉ and recognize the 'first syllable' /chaL/. Now you'd recall the preposed vowel⁵, to perhaps construct the 'second syllable' เลียง, except for one problem: this syllable generates the wrong tone, mid. So you'd have to remember to perform 'tone carrying' from the first syllable to arrive at the correct tone, rising. Phew!

Now let's do it the Thai way:

เฉลียง    (hall; corridor)

The power of this technique is that we don't have to introduce anything new in order to handle this case. The vowel orthography is handled just like we saw with เตียง  earlier, the cluster (ฉล) is handled just like we saw with ถนน  earlier, and the tone comes out correctly, without any special rules.

Would you like to try another one? See if you can work it out on your own: เจริญ . Draw the diagram if you need to.

d. - Refining the clustered consonant tone rule

Here are some further details on calculating the tone of these syllables. I recommend skipping this section if you just want to learn the basics.

First, recall that the sonorant consonants are those low-class consonants to which you can hum a tune, namely { ง, น, ม, ย, ร, ล, ว, ญ, ณ, ฬ }. They roughly correspond to the hummable English sounds { ng, n, m, y r, l, w }—try humming them.

Now as you learn Thai words, you'll notice that the second consonant in non-conforming clusters is almost always a sonorant. If, however, it's not, then the tone of the overall syllable will be determined according to the class of that second consonant.

Now we can state the full version of the clustered consonant tone rule: Such words are relatively few, so this is not a situation you need to worry about very much. Here are some examples with mid-class second consonant: แสดง , เสบียง , เผอิญ, เผดียง (and presumably also เสด็จ and เผด็จ although the distinction makes no difference due to their dead consonant endings). Here are some examples with high-class second consonant: เกษียณ , เกษียร. And finally, here are two examples with a low-class, non-sonorant second consonant: เฉพาะ , เผชิญ

By the way, no cluster can be composed from two mid-class consonants.

IV - Other Clusters

a. Cluster /บร-/ Using Sub-syllable /เบาะ-ร-/

We call clusters 'non-conforming' when it's in the nature of the two clustered consonants that they can't be merged together in their pronunciation. We insert /-a/, the minimum possible vowel sound, in order to ease the pronunciation, and the tone is still determined by the first consonant. Sometimes in Thai, however, a more significant vowel sound is implied between two consonants with no written vowel. This can occur with the cluster /บร-/, which appears with the vowel /บริ/ in many words. This syllable (not a valid word when standing alone) is pronounced /bawL riH/. For this example, we'll use a two-syllable word, like so:

บริการ    (to serve, help, assist, or support, to service; a service)

This word is pronounced /bawL riH gaanM/. Notice the second syllable uses the final /-aawn/ as discussed above. But let's focus on the first syllable by zooming in on its initial consonant cluster.

It might be best to think of this case as implying the stand-alone syllables /เบาะ/ and /ริ/, since thinking of it as a cluster doesn't offer any advantage. The spoken tone of the second "syllable" /ริ/ will always will always be high.

b. Cluster รร

[this section is still under construction] Kumchai considers รร an instance of false consonant cluster. There are two types:

• เป็นตัวสกดด้วยกัน (รร acting as vowel /-a/) {ตรรค, ธรรม, อรรถ, etc.}
• การันต์ตัวหลัง (รร acting as /-an/).

Summary

This whirlwind tour has examined the major features of Thai syllables, starting from a point of no Thai reading experience. Working with our Syllable Anatomy diagrams is a powerful technique that encourages spatial visualization of their phonetic construction. The method requires that initial consonant clusters be treated much the same as simple initial consonants. In particular, we've seen that it's important not to break consonant clusters out into separate syllables. They must remain clustered so that we can determine the proper tone and more easily read syllables with preposed vowels. Surprisingly, this way of thinking of clusters, while much closer to the conception of native Thais, is not taught in most beginning and intermediate Thai-learning texts for foreigners.

This article by Glenn Slayden
Thanks to David Rubin, Rikker Dockum, and Richard Wordingham
originally posted: January 22, 2008
updated: March 23, 2008