As mentioned in the previous post, when considering the spelling of a word in Thai, the consonant class influences the tone of the word. There are three consonant classes: low, mid, and high.

We will start with the High class consonants (HCC) first because I believe it is the easiest of the three.

The high class consonants are:

ข, ฉ, ฐ, ถ, ผ, ฝ, ศ, ษ, ส, ห

You will need to memorize this list. The HCC are the only consonants that can create a rising tone without the use of the อ๋ tone mark. The HCC cannot be used to create a mid-tone. If you hear a rising tone, chances are it uses an HCC. In the following rules I won’t go over every letter, but the rules apply to any of the HCC.

 

1. If a HCC is with a live (or no) ending consonant, and has no tone mark and no dead consonant, the tone is rising.

เขา

ขัน

ขา

สาม

ศาลา

ฝน

ถึง

 

2. If a HCC has a อ้ tone mark, and no dead consonant, the tone is falling.

เข้า

ขั้น

ข้า

ห้าม

ห้า

 

3. If a HCC is with a อ่ tone mark, and/or has a dead ending consonant, the tone is low.

ขัด

ขาด

หีบ

ฉิ่ง

ข่า

ข่าว

 

4. When the first syllable is an alone HCC without a visible vowel (and is not a consonant cluster), it becomes a low tone while the second consonant becomes an HCC. The ห is always silent if there is no vowel with it – it solely exists to modify the tone of the word.

สยาม sa2yaam5

สนาม sa2naam5

ขนม ka2nom5

หลาย laai5

หน้า naa3

เหรอ law5

เหงา ngao5

ใหญ่ yai2