Passive Voice Construction In Thai

[snowleopard]

When passive voice is used in English,the action described by the verb can be either pleasant or unpleasant!

Example 1:

I was given these wonderful presents by my fiancee.

These wonderful presents were given to me by my fiancee.

Example 2.

Game warden Jim was first shot by a poacher and then eaten by hungry lions.(very pleasant for the lions )

I got fined for poaching.(very unpleasant for a leopard )

It seems to me that the passive voice in Thai is mainly used for describing unpleasant happenings.

This passive voice is formed by using either the auxiliary ถูก="thook" or โดน="don".

Examples

เขาถูกสุนัขกัด "kao thook soo-nak gut"=He was bitten by the dog.

นักเรียนโดนครูตี "nak-ree-an don kroo dtee"=The pupil received corporal punishment at the hands of the teacher.

What's the best way of expressing life's pleasant moments in Thai by using its passive voice construction- like when you get hit with several expensive surprises on your birthday while passively receiving them with your mouth agape?

Right now I can think of ได้รับจาก="dai rahp jahk" for such an incident ;but I'm sure there are several other ways.

Get on the case folks and begin brainstorming for solutions!

Cheers.

Snowleopard.

[meadish_sweetball]

Hi Snowleopard and all you other language junkies who come here for your daily fix,

I happened to take a closer look at the Thai passive a few years ago, and it is generally accepted among Thai linguists that SUBJECT "thuuk" / "doon" (AGENT) + VERB are both used in negative contexts, whereas SUBJECT + "dai rap" + VERB or SUBJECT + "dai rap" + NOUN is the one to choose for most positive and neutral contexts.

However, it should be noted that the use of passive construction is used with a lot more restriction in Thai writing (except for some translations from other languages)... and that it is advisable for the translator to at least always consider choosing the active voice instead.

David Smyth also mentions the following pattern (in his 'Thai: An Essential Grammar' ):

Passive expressions like 'it is well known that...', 'it is generally accepted that...' and so on, can be formed by using the pattern

pen thii + VERB + kan + waa ...:

pen thii saap kan dii waa

เป็นที่ทราบกันดีว่า ...

It is well known that ...

pen thii yawm rap kan dooy thua pai waa ...

เป็นที่ยอมรับกันโดยทั่วไปว่า ...

It is generally accepted that ...

[username2004]

Hello meadish_sweetball and snowleopard:

Here's something I'd love to share. Thais have borrowed from the English language passive voice, as you can always see in journalistic writing style: ตาย (tai) 2 บาดเจ็บ (baad jeb) 4 = 2 Dead, 4 Injured. The only GENUINE Thai passive voice is "thuuk" / "doon" (AGENT) + VERB are both used in negative contexts," as meadish_sweetball explains; other passive voice forms are not genuine Thai but often used.

[meadish_sweetball]

Thank you very much for the clarification, Username2004:

It is great to become aware of the fine nuances in the language, and even better to know when they may mean something ambiguous or rude...

I believe I have also heard people use "ทำร้ายตัวเอง" (tham raay tua eeng); literally for "masturbate", in a joking way. Can you confirm this please, Username2004?

Cheers,

Meadish

[username2004]

meadish_sweetball, you are right, but I hardly hear anyone use the word. I should have been more socialized!!!!!!!!

[sabaijai]

While doing graduate study in linguistics at university, I wrote one of my research papers on the Thai passive voice. At the time I had access to several previous studies on the topic from PhD students at Chula, and I also surveyed native speakers, sampled textbooks of the time, etc.

As has already been noted the use of the thuuk/dohn construction is generally negative in spoken Thai. However in scientific Thai, one does find the thuuk construction (but not dohn, which is more colloquial anyway) used in a neutral fashion, in the same way the passive voice is used in English technical writing (but far less frequently).

That was nearly 20 years ago, and I don't read Thai scientific writing much anymore, so can't say whether this is something that still holds true.

[Johpa]

Passive expressions like 'it is well known that...', 'it is generally accepted that...' and so on, can be formed by using the pattern

pen thii + VERB + kan + waa ...:

pen thii saap kan dii waa

เป็นที่ทราบกันดีว่า ...

It is well known that ...

pen thii yawm rap kan dooy thua pai waa ...

เป็นที่ยอมรับกันโดยทั่วไปว่า ...

It is generally accepted that ...

I was taught by my Thai Achaan that these constructions noted that Thai, especially in its more formal and written forms, is more a topic focused language than a subject focused language. Thus one is more likely to begin a sentence:

As for the stars in the night sky...

as opposed to

The stars in the night sky....

[OOLEEBER]

Hi Guys,

Sorry to butt in here with a change of topic but you 5 folk seem to be the most informed here (and the most enthusiastic). I know nothing of linguistics and there are some key phrases or words you use that, if I knew the meaning I feel would open up a whole new world of understanding for me.

I mentioned in an earlier post that I wish I had studied English further at school. but alas.......

Here is the level of my lack of knowlege.

1) Noun - naming word: chair, bike etc

2) Adjective - can't remember, is that a describing word? Like Fat or fascinating?

3) Verb - To Do (the auto pilot in my brain is still working I think) ie.. - no, I'm not sure. Does that mean I'm "going to go shopping" and "going" is the verb?

Jeez I feel really stupid now.

But my point is I know so very little to be able to deconstruct and discuss the language and you guys understand these words as well as you know the names of the fruit at the market. And I'd love to learn too. I could look the words up in the dictionary but it's not as much fun and not nearly as informative as hearing it from a (or several) human being(s).

So far (just in this thread) the words who's meanings have escaped me are:

Passive voice

Agent

Auxiliary

There must be so many more and I really should buy a book on the subject. To be honest though, I can't remember being taught any of this at school. All I remember is reading 'To Kill a Mocking Bird'.

Anyway, please forgive me if I'm out of line and out of context with this intrusion and I will accept your correction on my post in this thread without embarrassment but any advice on any of the above that might open my eyes further in the world of language would be gratefully received.

Cheers

[snowleopard]

Hi Guys,

Sorry to butt in here with a change of topic but you 5 folk seem to be the most informed here (and the most enthusiastic). I know nothing of linguistics and there are some key phrases or words you use that, if I knew the meaning I feel would open up a whole new world of understanding for me.

I mentioned in an earlier post that I wish I had studied English further at school. but alas.......

Here is the level of my lack of knowlege.

1) Noun - naming word: chair, bike etc

2) Adjective - can't remember, is that a describing word? Like Fat or fascinating?

3) Verb - To Do (the auto pilot in my brain is still working I think) ie.. - no, I'm not sure. Does that mean I'm "going to go shopping" and "going" is the verb?

Jeez I feel really stupid now.

But my point is I know so very little to be able to deconstruct and discuss the language and you guys understand these words as well as you know the names of the fruit at the market. And I'd love to learn too. I could look the words up in the dictionary but it's not as much fun and not nearly as informative as hearing it from a (or several) human being(s).

So far (just in this thread) the words who's meanings have escaped me are:

Passive voice

Agent

Auxiliary

There must be so many more and I really should buy a book on the subject. To be honest though, I can't remember being taught any of this at school. All I remember is reading 'To Kill a Mocking Bird'.

Anyway, please forgive me if I'm out of line and out of context with this intrusion and I will accept your correction on my post in this thread without embarrassment but any advice on any of the above that might open my eyes further in the world of language would be gratefully received.

Cheers

So far (just in this thread) the words who's meanings have escaped me are:

Passive voice

Agent

Auxiliary

Hi there Ollie and welcome onboard!I'm sure you're gonna love getting tangled up in the language threads around these fora.

Hope you'll learn the ropes quickly.

I'll try to give you some hints on the three words you asked about!

1.Passive Voice

Active voice is when the subject of the verb does the action while passive voice is when the subject has the action done towards him and receives it in a passive fashion.The object then becomes the agent doing the action.

For this construction,you need a transitive verb with an object.

Sentence 1:(single transtive verb)

Active Voice:"The snowleopard kills a deer."

Passive Voice:"A deer is killed by the snowleopard."

Sentence 2:(double transitive verb,i.e.2 objects)

Active Voice:"Mary gave Tom a kick in the groin."

Passive Voice 1"Tom was given a kick in the groin (by Mary)."

Passive Voice 2:"The kick in the groin was given to Tom by Mary."

2.Auxiliary Verb

It's a verb that helps in forming a tense,passive voice and such.

In the sentences,"I have read that thread" and "That post is nicely written",the "have and is " are the auxiliaries that are joined with past participle to form tense and voice.

3.Agent

This is the code name for the active force that performs the action in a sentence.

That's it!

I'm afraid that I'm not at liberty to divulge much more information about our top secret agent,who's sometimes referred to as... " 007", because all his dossiers are still classified!

If you really,really wanna know some more about this agent,...well,then I guess I could tell you a little something...but upon hearing it you would have to be immediately and permanently silenced by...

Just kidding;but,did you notice the passive voice construction in the last instance?

Let's see if somebody else can explain "the agent" even better.

When you've got some questions on Thai language just post them here;and,I'll try to help you out as much as possible.

If I can't,then I'm sure Username,Meadish or another knowledgeable linguist can jump in and deal with the issue successfully.

Cheers.

Snowleopard.

[snowleopard]

Hello meadish_sweetball and snowleopard:

Here's something I'd love to share. Thais have borrowed from the English language passive voice, as you can always see in journalistic writing style: ตาย (tai) 2 บาดเจ็บ (baad jeb) 4 = 2 Dead, 4 Injured. The only GENUINE Thai passive voice is "thuuk" / "doon" (AGENT) + VERB are both used in negative contexts," as meadish_sweetball explains; other passive voice forms are not genuine Thai but often used.

sabaijai Posted on Mon 2004-08-02, 17:57:25

As has already been noted the use of the thuuk/dohn construction is generally negative in spoken Thai. However in scientific Thai, one does find the thuuk construction (but not dohn, which is more colloquial anyway) used in a neutral fashion, in the same way the passive voice is used in English technical writing (but far less frequently).

Hi there Meadish,Username and Sabaijai!

I just came to think about this passive voice construction which I think could be used without either ถูก "toohk";or,โดน "dohn"!

เรื่องนี้เขียนโดยคุณเสือดาว "reu-ang nee kee-an doy kuhn seua-daow"This story is written by Mr Leopard.

It's not even negative!

What do you think about it guys?

Cheers.

Snowleopard.

[username2004]

Hello all!!!!!

OOLEEBER, welcome to the board, too.

snowleopard, your explanation is exceptional! But may I add that auxiallary verbs can sometimes be called "model verbs" or "helping verbs," and that these verbs are verbs that tell time.

I just came to think about this passive voice construction which I think could be used without either ถูก "toohk";or,โดน "dohn"! 

เรื่องนี้เขียนโดยคุณเสือดาว "reu-ang nee kee-an doy kuhn seua-daow"This story is written by Mr Leopard.

It's not even negative! 

What do you think about it guys? 

I think it's okay and often used in Thai writing these days, but again, it's not GENUINE Thai. It's English-borrowing Thai.

[OOLEEBER]

Thanks Guys,

For the welcome and the explanations. Snowleopard, I read your post twice and was mildly frustrated with myself for not understanding all of it but I just found a site explaining English grammar and lo and behold I now understand you.

I'll try to keep my posts limited to Thai queries now that I have a source for the grammatical questions although any links to Thai grammar or a brief overview would help greatly.

It's funny I believe I speak thai in the correct grammatical order but only because I copy everyone else but I don't know why sentences are constructed as they are.

Thanks Again - Have a great Sunday!

[sabaijai]

เรื่องนี้เขียนโดยคุณเสือดาว "reu-ang nee kee-an doy kuhn seua-daow"This story is written by Mr Leopard.

It's not even negative!

What do you think about it guys?

I'll take a leap here and say I don't think Thais would consider this a passive voice construction. The trouble is the slippery nature of Thai verbs, most of which can slide from active to stative, and transitive to intransitive, depending on the context. I suppose this is the main reason you don't see much passive voice in Thai as it's not as necessary, Thai verbs being so inherently flexible.

Thus the เขียน verb phrase in this case doesn't need to be relativised with โดย. In fact I don't think a native speaker would write เรื่องนี้เขียนโดยคุณเสือดาว but rather something along the lines of เรื่องนี้คุณเสือดาวได้เขียน.

[username2004]

Sabaijai,

I'll take a leap here and say I don't think Thais would consider this a passive voice construction.

Your post makes me think about this question: What is passive voice in Thai? I don't have the answer...

Thus the เขียน verb phrase in this case doesn't need to be relativised with โดย. In fact I don't think a native speaker would write เรื่องนี้เขียนโดยคุณเสือดาว but rather something along the lines of เรื่องนี้คุณเสือดาวได้เขียน.

The pattern in "เรื่องนี้เขียนโดยคุณเสือดาว" is quite common nowadays. Another example would be "หนังเรื่องนี้กำกับโดย Sabaijai" (This movie is directed by Sabaijai.)

เรื่องนี้คุณเสือดาวได้เขียน: A bit awkward. This sentence would be far more natural: เรื่องนี้คุณเสือดาวได้เขียนไว้เมื่อหลายปีก่อน (Snowleopard was written by snowleapard several years ago.)

--- ปรบมือ ----

[meadish_sweetball]

Ok, here goes. About 'agent':

In an active voice sentence, the one who actually does something is known as the subject.

Simon closed the door. Simon closes the door. Simon did close the door. Simon will close the door. Simon is about to close the door. Simon would have closed the door.

'Simon' is the subject.

In a passive voice sentence, the person who performs the action described, is the agent, but the SUBJECT of the sentence is something else. Example:

The door was closed by Simon.

'The door' is the subject. 'Was closed' is the verb. 'Simon' is the agent.

I hope that clarifies something, at least!

Cheers,

Meadish

[OOLEEBER]

Very clear I think?

"the term agent was explained by meadish to ooleeber".

"agent" is the subject

"Meadish" is the Agent

"explained" is the Verb

But does that make "ooleeber" the 2nd subject or something else?

This is fascinating!!

Oh! and in the active voice, what does that make the door? Just a noun?

Thanks

[sabaijai]

เรื่องนี้คุณเสือดาวได้เขียน: A bit awkward. This sentence would be far more natural: เรื่องนี้คุณเสือดาวได้เขียนไว้เมื่อหลายปีก่อน (Snowleopard was written by snowleapard several years ago.)

Exactly, I had meant to add an elipsis (. . .) at the end as it would have to include a time frame . . .

When you say snowleopard's construction was quite common nowadays, are you saying it's more natural than my non-โดย example? The X โดย X phrase seems to me to be a relatively recent phenom (which I guess is why you said "nowadays"?), perhaps even an import. I don't hear it that much except from newscasters on TV, or perhaps I just run in non-literary circles ...

Edited August 9, 2004 by sabaijai

[meadish_sweetball]

Ok - now we get to the stage where we need to separate 'parts of speech' from 'sentence constituents'.

It was a while ago since I studied linguistics, and there are definitely people here whose knowledge within this subject is greater than mine, but here is an attempt at a definition anyway:

'Parts of speech' is used to divide words into different categories more or less in isolation, whereas 'sentence constituents' are used to describe the FUNCTION of the words IN CONTEXT - i.e. within a sentence.

When we compared sentences above, and used the terms SUBJECT and AGENT, we were talking about the names of sentence constituents, whereas "noun" and "pronoun" and "adjective", etc. are parts of speech.

Meadish is not sure he can explain this difference properly.

In terms of parts of speech, we can categorize the words in the above sentence as follows:

'Meadish' is a NOUN (a proper noun in fact).

'is' is a VERB.

'not' is an ADVERB

'sure' is an ADJECTIVE.

'he' is a PRONOUN ('instead of nouns', noun replacement words')

'can' is a VERB (an AUXILIARY VERB)

'explain' is also a VERB

'this' is a PRONOUN

'difference' is a NOUN

'properly' is an ADVERB (like adjectives describe nouns, ADVERBS describe VERBS, other ADVERBS and ADJECTIVES)

Now, if we turn to 'sentence constituents', we use a different terminology. Please note that it is not clear-cut which terminology or system to use. *

I will come back with this analysis later, unless somebody else would care for doing it instead of me.

This may be a little confusing, but I am sure you can find a web page out there which explains the difference more thoroughly. I will be back later with more info, right now I have to get back to work...

* I have been taught to analyse sentences more or less according to the tradition of Noam Chomsky, the US linguist. His views of linguistics, as well as his political views, are currently hotly debated

[Boon Mee]

"I have been taught to analyse sentences more or less according to the tradition of Noam Chomsky, the US linguist. His views of linguistics, as well as his political views, are currently hotly debated"

Not to stray off track here but sincerely agree with your statement re. Chomsky! The man should have been deported to some Communist country a long time ago.

p.s. you guys are doing a terrific job here in this language thread. Thanks for all the great help!

[sabaijai]

Noam's thoughts on linguistics, specifically the acquisition of syntax, fossilised a long time ago and have been superceded by several intervening theories in the meantime. He pretty much transferred his "Deep Structure" ideas about syntax -- a theory that he never was able to prove since it's an untestable idea and is hence not a true 'hypothesis' in the scientific meaning of the word -- wholesale into his political science, out of which he has made a lot more money than he ever did as a linguist. Most linguists don't take him seriously anymore, and neither do most political scientists. He's nonetheless very adept at selling his arguments to laypeople.

Beyond Chomsky

Edited August 9, 2004 by sabaijai

[Boon Mee]

Noam's thoughts on linguistics, specifically the acquisition of syntax, fossilised a long time ago and have been superceded by several intervening theories in the meantime. He pretty much transferred his "Deep Structure" ideas about syntax -- a theory that he never was able to prove since it's an untestable idea and is hence not a true 'hypothesis' in the scientific meaning of the word -- wholesale into his political science, out of which he has made a lot more money than he ever did as a linguist. Most linguists don't take him seriously anymore, and neither do most political scientists. He's nonetheless very adept at selling his arguments to laypeople.

Beyond Chomsky

sabaijai,

Please qualify that as some lay people!

p.s. my last word on this creep.

[OOLEEBER]

Love your stuff here guys!

O

[OOLEEBER]

And thanks Meadish,

I'm still trying to get my head around your very kind and patient explanation. Not to mention scouring the web for info.

I think I now understand the difference but find it hard to obtain a glossary of sentence constituents. Still looking.

Good onya matey.

ooleeber

[Richard W]

But may I add that auxiallary verbs can sometimes be called "model verbs" or "helping verbs," and that these verbs are verbs that tell time.

No!

'Helping verb' does mean the same as 'auxiliary verb'.

All 'modal verbs' are 'auxiliary verbs', but not all 'auxiliary verbs' are 'modal verbs'. It so happens that almost all English modal verbs indicate present tense or past tense ('must' is an exception - it does not distinguish them), though the past tense of a modal verb often has nothing to do with past time. For example, the difference between 'But may I add...' and 'But might I add' is largely one of diffidence.

In the quoted sentence:

'may', 'can' are modal verbs.

'be' is an auxiliary verb, is not a modal verb, and does not indicate time but voice!

Edited August 10, 2004 by Richard W

[username2004]

Richard, thanks! I always had that misunderstanding - but now, I am enlightened!

[snowleopard]

Ok, here goes. About 'agent':

In an active voice sentence, the one who actually does something is known as the subject.

Simon closed the door. Simon closes the door. Simon did close the door. Simon will close the door. Simon is about to close the door. Simon would have closed the door.

'Simon' is the subject.

In a passive voice sentence, the person who performs the action described, is the agent, but the SUBJECT of the sentence is something else. Example:

The door was closed by Simon.

'The door' is the subject. 'Was closed' is the verb. 'Simon' is the agent.

I hope that clarifies something, at least!

Cheers,

Meadish

Ok, here goes. About 'agent':

In an active voice sentence, the one who actually does something is known as the subject.

Hi Meadish et al.

In pedagogical layman terms,you've given Oliver some lucid explanations with fine examples re the "AGENT" here,but let me provide some additional,newly declassified information that will illuminate the dark world of espionage even more-and which can also be very helpful in our quest to uncover and expose the secret agent's real identity...

Who's the agent?

First Agent=Active Voice Agent (i.e.subject):

In active voice,the subject,himself, is the agent who is doing the action.

Example 1=active voice where the subject is the agent:

a.)"It's now been confirmed by our agency that it was indeed our AGENT 007 who shot the bullet that penetrated the victim's skull with such pinpoint accuracy."

Second Agent=Passive Voice Agent:

In passive voice,the subject is NOT the agent but rather the subject,himself, is now at the receiving end of the action which is performed by the real agent.

Example 2=passive voice where the subject is not the agent:

b.)"The mole was assassinated by our secret AGENT 007 in Moscow a few moments ago."

In both examples above,the "double" agent is THE agent;but in many other passive voice constructions,the agent's role is often omitted and he's working undercover deep inside the sentence

In the instance where the agent is omitted,both his role and whereabouts are no secret to us here at the agency,and others,who have been initiated into the use of grammar and who work with decoding intelligence on a daily basis.

Third Agent=Passive Voice Agent Working Undercover:

WARNING:..CLASSIFIED!..."For Your Eyes Only"...once read,the following message re the agent's real identity must be deleted and everyone else in the know,outside of our language board,must be terminated!

Example 3=when the prepositional phrase which describes the agent is omitted but his role is implicitly understood by the reader:

c.)/By our agency/..."Our undercover agent has been codenamed... "007",and that's the name we have clandestinely leaked to the Russian moles of the KGB,but her real name is of course Blonde..."Jane Blonde"!

Cheers.

The Spymaster,codenamed Snowleopard.

Meadish is not sure he can explain this difference properly.

In terms of parts of speech, we can categorize the words in the above sentence as follows:

'Meadish' is a NOUN (a proper noun in fact).

'is' is a VERB.

'not' is an ADVERB

'sure' is an ADJECTIVE.

'he' is a PRONOUN ('instead of nouns', noun replacement words')

'can' is a VERB (an AUXILIARY VERB)

'explain' is also a VERB

'this' is a PRONOUN

'difference' is a NOUN

'properly' is an ADVERB (like adjectives describe nouns, ADVERBS describe VERBS, other ADVERBS and ADJECTIVES)

Meadish is not sure he can explain this difference properly.

'this' is a PRONOUN

The second thing I wanna point out is about your classification of the word "this"!

"This" can be either a demonstrative pronoun or a demonstrative adjective,depending on its function in the phrase.

In your example,"this" is actually used as a demonstrative adjective because it modifies the noun "difference"!

Snowleopard.

[OOLEEBER]

Thanks snowleopard but Jeez ! I'm going to have to read that again tomorrow before I've had my first 2 beers of the day.

Someones birthday today - you know how it is.

Sincere thanks - I'm really enjoying this journey in language but for now I'm off to find Miss Moneypenny.

Cheers

O

[snowleopard]

Hi there Username,Meadish,Sabaijai,Richard et al.

I've come up with some more sentences in Thai which I think are passive voice constructions in their own right without using the ถูก (toohk) or the โดน (dohn) as auxiliaries.

Here they are...

1.หลังคาของบ้านเราปกคลุมด้วยหิมะ "lang-kaa korng baan raow pok-kluhn doo-ay he-ma"=The roof of our house is covered with snow.

2.เธอกำลังทำอะไรอยู่....อาหารยังไม่ได้กินเลยและน้ำยังไม่ได้อาบด้วย "teur gum-lahng tahm ah-rai yoo?...ah-haan yahng mai dai gin leuy lae nahm yahng mai dai ahp doo-ay"=What are you doing now?...Your food hasn't been eaten yet and no shower has been taken either.

3.ถนนมันท่วมอยู่ "tah-nohn man too-am yoo"=The streets are flooded.

Do you think the above sentences qualify in the passive voice category?

Your feedback on that would be appreciated.

Cheers.

Snowleopard.

[Richard W]

The basic purpose of the passive is to de-emphasis the agent, even exclude him altogether. These sentences, where the agent is omitted, and the patient becomes the subject, are thus semantically passive. However, there is nothing in the form of these sentences that marks them as passive - you have to know that the verb is transitive to realise that there is something odd about the sentences. They are parallel to sentences with หัก /hak/ 'break', which is always intransitive.

They may be compared to transitive and intransitive English verbs such as 'break', 'burn', 'cook' and 'lengthen', which may be:

• transitive and active (both agent and, normally, patient expressed),
  
• transitive and passive (patient and optionally agent expressed) or
  
• intransitive (and active) (normally patient only expressed)
  

English has a lot of such verbs, but there are also a few in Latin. (French and German tend to use the reflexive where English would use the intransitive form.)

The difference in Thai is that it seems that every transitive verb may be used intransitively.

I would say that these sentences are not passive, but note that the verb is being used intransitively.

[snowleopard]

The basic purpose of the passive is to de-emphasis the agent, even exclude him altogether.  These sentences, where the agent is omitted, and the patient becomes the subject, are thus semantically passive.  However, there is nothing in the form of these sentences that marks them as passive - you have to know that the verb is transitive to realise that there is something odd about the sentences.  They are parallel to sentences with หัก /hak/ 'break', which is always intransitive. 

They may be compared to transitive and intransitive English verbs such as 'break', 'burn', 'cook' and 'lengthen', which may be:

• transitive and active (both agent and, normally, patient expressed),
  
• transitive and passive (patient and optionally agent expressed) or
  
• intransitive (and active) (normally patient only expressed)
  

English has a lot of such verbs, but there are also a few in Latin.  (French and German tend to use the reflexive where English would use the intransitive form.)

The difference in Thai is that it seems that every transitive verb may be used intransitively.

I would say that these sentences are not passive, but note that the verb is being used intransitively.

However, there is nothing in the form of these sentences that marks them as passive - you have to know that the verb is transitive to realise that there is something odd about the sentences. They are parallel to sentences with หัก /hak/ 'break', which is always intransitive.

หัก /hak/ 'break', which is always intransitive

Really Richard!

How about this Thai sentence which uses the verb หัก "hahk"?

เขาแขนหักเนื่องจากอุบัติเหตุทางรถจักรยานสองล้อ "kaow kaen hahk neung-jaahk oba-dtee-heaht taang rot-jahk-a-yaahn sorng looh""=His arm was broken in a bicycle accident.

Did the arm "actively" break itself in the accident or did he break his arm on purpose?

Self-destructive like Usama's kamikaze pilots?

Cheers.

Snowleopard.