As mentioned in the previous three posts, 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 finish with the hardest consonant class – the Low class consonants (LCC). More than half of all Thai consonants are of the low class. If you had already memorized the High and Mid classes, you would automatically know that any other consonant is of the low class.

The low class consonants are:

ค, ฆ, ง, ช, ซ, ฌ, ญ, ฑ, ฒ, ณ, ท, ธ, น, พ, ฟ, ภ, ม, ย, ร, ล, ว, ฬ, ฮ

You will need to memorize this list (or at least memorize the High and Mid classes). Contrary to it’s name, the LCC are the only consonants that cannot achieve the low tone. It is also the only consonant class which is affected by vowel length. In the following rules I won’t go over every letter, but the rules apply to any of the LCC.

 

1. If an LCC has a live ending consonant, and no tone mark, the tone is mid.

นาน

ควาย

ธง

คง

 

2. If an LCC has a long vowel with no ending consonant, and no tone mark, the tone is mid.

รา

นา

งู

ลา

 

3. If an LCC has a short vowel and a dead (or no) ending consonant, and no tone mark, the tone is high.

รัก

นัก

นัด

คะ

นะ

 

4. If an LCC has a dead ending consonant, a long vowel, and no tone mark, the tone is falling.

ราก

ยาก

มาก

 

5. If an LCC has a อ้ tone mark, the tone is high.

ร้าน

ค้อน

ฟ้า

 

6. If an LCC has a อ่ tone mark, the tone is falling.

ย่าง

ง่าย

ช่วง

ฆ่า

เฒ่า