English

Where the action moves: ขึ้น, ออก, เข้า, ไว้

The Thai verb has no prefixes: the direction is brought by a second word after the verb. khan khuen — screw in, literally "turn upward"; khai ok — unscrew, "lead outward". What English packs into "in-" and "out-" here are separate words with meanings of their own. For example: “ขัน สกรู เข้า ไป” — Screw the screw inward. A rule from the Thai course: worked out on examples, not memorized as a wording.

Updated September 1, 2026 · Lingofly

How it works

The Thai verb has no prefixes: the direction is brought by a second word after the verb. khan khuen — screw in, literally "turn upward"; khai ok — unscrew, "lead outward". What English packs into "in-" and "out-" here are separate words with meanings of their own.

You have long known these words as verbs of their own: khao — enter, ok — exit, khuen — rise. After another verb they only point the way: sai khao pai — insert inside; wang long — put down.

A special word is ไว้ (вай): after a verb it means "leave in place". kep wai — keep, gather and leave; pae wai — stick and not touch. English "leave it there" hides exactly here.

Everything can be gathered back through klap: khai klap — screw back. Direction in Thai is not a form of the verb but a second word you choose anew every time.

Table

Where the action moves: ขึ้น, ออก, เข้า, ไว้
DirectionWordReadingExample
up, into the threadขึ้นkhuenขัน ขึ้น — screw in
outwardออกokไข ออก — unscrew
inwardเข้าkhaoใส่ เข้า ไป — insert
downลงlongวาง ลง — put down
leave in placeไว้waiเก็บ ไว้ — keep for oneself
backกลับklapไข กลับ — screw back
together, to the endรวมruamรวม ไว้ — gather together

By example

  • ขัน สกรู เข้า ไป
    кхан сакруу кхао пай
    Screw the screw inward
  • ไข สกรู ออก
    кхай сакруу оок
    Unscrew the screw outward
  • แปะ กาว ไว้ ให้ แห้ง
    пэ као вай хай кхэнг
    Stick it and leave it to dry

How the rule settles in your head

A rule is not memorized from an explanation. It is memorized from an attempt to use it and a mistake — that is why the app delivers it mixed in with words, not as a separate lesson: it resurfaces exactly where you forgot it.

Frequently asked

Where the action moves: how does it work in Thai?

The Thai verb has no prefixes: the direction is brought by a second word after the verb. khan khuen — screw in, literally "turn upward"; khai ok — unscrew, "lead outward". What English packs into "in-" and "out-" here are separate words with meanings of their own.

What does it look like in a Thai example sentence?

“ขัน สกรู เข้า ไป” (кхан сакруу кхао пай) — Screw the screw inward. A rule is easier to test on sentences like this than to memorize as a wording: what surfaces in conversation is the sentence.

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