Like in English, the Thai language differentiates between ‘to think’ and ‘to know’. However, Thai is a bit more complicated in that both words can be omitted from a context-obvious sentence, and ‘to know’ is divided up into three different words.
The first word we’ll look at is ‘to think’, or kid4 คิด. This word has the exact same meaning as in English, so let’s just jump into examples . . .
think
Kid4
คิด
Have good thoughts.
Kid4 dee1
คิดดี
thought
Kwaam1 kid4
ความคิด
I think that . . .
Pom5 kid4 waa3
ผมคิดว่า . . .
[You] thought wrong.
Kid4 mai3 tuuk2
คิดไม่ถุก
The next word is ruu4 รู้, or ‘to know’ (a fact). Just like kid4 above, it’s a very common word that any beginning Thai language learner should know.
know
Ruu4
รู้
I know that . . .
Pom5 ruu4 waa3
ผมรู้ว่า . . .
You know good and well that . . .
Kun1 ruu4 dee1 waa3
คุณรู้ดีว่า . . .
[I] know [that] already.
Ruu4 laew4 krap4
รู้แล้วครับ
Unlike in English where you use the same word ‘know’ for both facts and people, in Thai there is a word for each. To know a person, you’d use ruu4jak2 รู้จัก as in the below examples.
To know [someone]
Ruu4 jak2
รู้จัก
I know him.
Pom5 ruu4jak2 kow5
ผมรู้จักเขา
We’ve known each other for a long time.
Row1 ruu4jak2 gan1 naan1
เรารู้จักกันนาน
Back when I was a beginner, I got really confused with the word waa3 ว่า which means ‘that’. People kept saying “I that …” and it took me a bit to figure out it was a contextual abbreviation. You may have already noticed this word in some of the above examples. It turns out in Thai that you can remove the words รู้ and คิด when they come before ว่า in certain instances. But be careful, depending on the instance, it might mean ‘think’ instead of ‘know’.
that
Waa3
ว่า
I know that . . .
Pom5 ruu4 waa3
ผมคิดว่า . . .
I know that . . . <- abbreviated from context
Pom5 waa3
ผมว่า . . .
I knew it! (implying it was dead obvious; said after the truth was revealed, confirming your suspicion)
Waa3 laew4
ว่าแล้ว
In the above sentence, if you don’t abbreviate it as such, it would take 6 words to say the same thing. Thai is a lazy mans dream language!
If you are talking to someone much older, or more important, or higher up than you, you should instead use ทราบ saab3 to be polite. Saab3 means ‘to know’ and can be used in place of ruu4 รู้.
Know (formal)
Saab3
ทราบ
I know that . . .
Pom5 saab3 waa3
ผมทราบว่า . . .
