How To Make Negative Sentences In Thai

Introduction

Learning how to say that you do not want something, cannot do something, have not finished, or do not understand is essential for everyday communication. Fortunately, making negative sentences in Thai is usually easier than making negative sentences in English.

The most important negative word is:

ไม่ — mai — not, do not

It normally appears before a verb or adjective.

For example:

ผมกินอาหารเผ็ด
Phom kin ahaan phet.
I eat spicy food.

Add mai before the verb:

ผมไม่กินอาหารเผ็ด
Phom mai kin ahaan phet.
I do not eat spicy food.

Thai verbs do not change when a sentence becomes negative. There is no need to add separate words equivalent to “do,” “does,” or “did.”

However, different patterns are needed for meanings such as “not yet,” “cannot,” “is not,” “do not have,” and “never.” This guide explains the main ways to form negative sentences in Thai, with Thai script, romanisation, English meanings, and practical examples.

👉 “Readers practicing negative sentences in Thai may also explore traditional Thai herbs used in natural wellness practices for additional cultural context and useful vocabulary.”

The Basic Negative Word Mai

The most common pattern is:

Subject + mai + verb

Examples:

ผมไม่ไปครับ
Phom mai pai khrap.
I am not going.

ฉันไม่กินเนื้อค่ะ
Chan mai kin nuea kha.
I do not eat meat.

เขาไม่ทำงานวันนี้
Khao mai tham ngan wan ni.
He or she is not working today.

เราไม่เข้าใจ
Rao mai khao jai.
We do not understand.

The negative word mai appears immediately before the action being made negative.

This basic pattern is the foundation for most negative sentences in Thai.

Thai Verbs Do Not Change

English may use different negative forms:

• I do not eat.
• He does not eat.
• We did not eat.

Thai keeps the verb unchanged:

ผมไม่กิน
Phom mai kin.
I do not eat.

เขาไม่กิน
Khao mai kin.
He or she does not eat.

พวกเราไม่กิน
Phuak rao mai kin.
We do not eat.

The verb kin, meaning “eat,” remains the same. Only mai is added before it.

Time is usually shown through context or additional time words.

เมื่อวานผมไม่กินข้าว
Muea wan phom mai kin khao.
Yesterday, I did not eat.

พรุ่งนี้ผมไม่ไปทำงาน
Phrung ni phom mai pai tham ngan.
Tomorrow, I will not go to work.

This makes the basic grammar of negative sentences in Thai relatively straightforward.

Making Adjectives Negative

The word mai also appears before adjectives.

The pattern is:

Subject or noun + mai + adjective

Examples:

อาหารไม่เผ็ด
Ahaan mai phet.
The food is not spicy.

ห้องไม่ใหญ่
Hong mai yai.
The room is not big.

กาแฟไม่ร้อน
Kafae mai ron.
The coffee is not hot.

ร้านนี้ไม่แพง
Ran ni mai phaeng.
This shop is not expensive.

Thai does not normally require a separate word for “is” before an adjective.

Positive:

อาหารอร่อย
Ahaan aroi.
The food is delicious.

Negative:

อาหารไม่อร่อย
Ahaan mai aroi.
The food is not delicious.

This direct adjective pattern is frequently used in everyday negative sentences in Thai.

Saying “I Do Not Understand”

One of the most useful beginner phrases is:

ไม่เข้าใจ — mai khao jai — do not understand

Examples:

ผมไม่เข้าใจครับ
Phom mai khao jai khrap.
I do not understand.

ฉันไม่เข้าใจค่ะ
Chan mai khao jai kha.
I do not understand.

The pronoun can be omitted:

ไม่เข้าใจครับ/ค่ะ
Mai khao jai khrap/kha.
I do not understand.

Other useful learning phrases include:

ฟังไม่เข้าใจครับ/ค่ะ
Fang mai khao jai khrap/kha.
I do not understand what I hear.

อ่านไม่เข้าใจครับ/ค่ะ
An mai khao jai khrap/kha.
I do not understand what I read.

พูดภาษาไทยไม่เก่งครับ/ค่ะ
Phut phasa Thai mai keng khrap/kha.
I do not speak Thai well.

Saying “I Do Not Know”

The expression is:

ไม่รู้ — mai ru — do not know

Examples:

ผมไม่รู้ครับ
Phom mai ru khrap.
I do not know.

ฉันไม่รู้ค่ะ
Chan mai ru kha.
I do not know.

ไม่รู้ว่าเขาอยู่ที่ไหน
Mai ru wa khao yu thi nai.
I do not know where he or she is.

ผมไม่รู้ราคา
Phom mai ru rakha.
I do not know the price.

In natural conversation, simply saying mai ru with the appropriate polite particle is often enough.

This is one of the most practical negative sentences in Thai for beginners.

Saying “I Do Not Want”

Thai uses different words depending on whether you are rejecting something or saying that you do not want to perform an action.

Mai Ao For Refusing Something

ไม่เอา — mai ao — do not want, will not take

Examples:

ไม่เอาครับ
Mai ao khrap.
No, thank you. I do not want it.

ไม่เอาถุงค่ะ
Mai ao thung kha.
I do not want a bag.

ผมไม่เอาอันนี้ครับ
Phom mai ao an ni khrap.
I do not want this one.

This expression is common in shops, markets, restaurants, and everyday conversation.

Mai Yak For Not Wanting To Do Something

ไม่อยาก — mai yak — do not want to

Examples:

ผมไม่อยากไปครับ
Phom mai yak pai khrap.
I do not want to go.

ฉันไม่อยากกินค่ะ
Chan mai yak kin kha.
I do not want to eat.

เขาไม่อยากทำงานวันนี้
Khao mai yak tham ngan wan ni.
He or she does not want to work today.

These forms help learners create useful negative sentences in Thai without sounding overly complicated.

Saying “Not Yet” With Yang Mai

The expression:

ยังไม่ — yang mai — not yet

appears before the verb or adjective.

The pattern is:

Subject + yang mai + verb

Examples:

ผมยังไม่กินข้าวครับ
Phom yang mai kin khao khrap.
I have not eaten yet.

เขายังไม่มา
Khao yang mai ma.
He or she has not arrived yet.

งานยังไม่เสร็จค่ะ
Ngan yang mai set kha.
The work is not finished yet.

ฉันยังไม่พร้อมค่ะ
Chan yang mai phrom kha.
I am not ready yet.

The subject is often omitted:

ยังไม่รู้ครับ
Yang mai ru khrap.
I do not know yet.

ยังไม่แน่ใจค่ะ
Yang mai nae jai kha.
I am not sure yet.

The yang mai pattern is essential for natural negative sentences in Thai because it shows that a situation may change later.

Answering “Have You…Yet?”

A common Thai question uses:

…หรือยัง — rue yang — …yet?

Example:

กินข้าวหรือยังครับ
Kin khao rue yang khrap?
Have you eaten yet?

Positive answer:

กินแล้วครับ
Kin laeo khrap.
Yes, I have eaten already.

Negative answer:

ยังไม่ได้กินครับ
Yang mai dai kin khrap.
I have not eaten yet.

A shorter answer is:

ยังครับ/ค่ะ
Yang khrap/kha.
Not yet.

Another example:

ทำเสร็จหรือยัง
Tham set rue yang?
Have you finished?

ยังไม่เสร็จ
Yang mai set.
Not finished yet.

Saying “Cannot” With Mai Dai

The expression:

ไม่ได้ — mai dai — cannot, did not, was not able to

is often used to show inability, impossibility, or that an action did not happen.

The exact position depends on the meaning.

Verb + Mai Dai For Inability

The pattern is:

Subject + verb + mai dai

Examples:

ผมว่ายน้ำไม่ได้ครับ
Phom wai nam mai dai khrap.
I cannot swim.

เขาพูดภาษาไทยไม่ได้
Khao phut phasa Thai mai dai.
He or she cannot speak Thai.

วันนี้มาไม่ได้ค่ะ
Wan ni ma mai dai kha.
I cannot come today.

เด็กเข้าไม่ได้ครับ
Dek khao mai dai khrap.
Children cannot enter.

This is one of the most common patterns used in negative sentences in Thai.

The Difference Between Mai + Verb And Verb + Mai Dai

Compare these two sentences:

ผมไม่ไป
Phom mai pai.
I am not going.
I do not go.

ผมไปไม่ได้
Phom pai mai dai.
I cannot go.

The first sentence expresses a decision, habit, or simple negative action.

The second sentence expresses inability or impossibility.

Another comparison:

เขาไม่พูดภาษาไทย
Khao mai phut phasa Thai.
He or she does not speak Thai.

เขาพูดภาษาไทยไม่ได้
Khao phut phasa Thai mai dai.
He or she cannot speak Thai.

The position of the negative changes the meaning. Understanding this difference helps beginners make clearer negative sentences in Thai.

Mai Dai Before A Verb

The expression mai dai can also appear before a verb to show that an action did not happen.

Examples:

เมื่อวานผมไม่ได้ไปทำงาน
Muea wan phom mai dai pai tham ngan.
Yesterday, I did not go to work.

เขาไม่ได้โทรมา
Khao mai dai thorasap ma.
He or she did not call.

ฉันไม่ได้ซื้อค่ะ
Chan mai dai sue kha.
I did not buy it.

เราไม่ได้พูดแบบนั้น
Rao mai dai phut baep nan.
We did not say that.

This pattern often emphasises that the event did not occur.

Compare:

ผมไม่กินเนื้อ
Phom mai kin nuea.
I do not eat meat.

เมื่อวานผมไม่ได้กินเนื้อ
Muea wan phom mai dai kin nuea.
Yesterday, I did not eat meat.

The first describes a general habit. The second refers to a specific past event.

Saying “Is Not” With Mai Chai

The expression:

ไม่ใช่ — mai chai — is not, am not, are not, that is incorrect

is used to reject an identity, category, ownership claim, or statement.

Examples:

ผมไม่ใช่คนไทยครับ
Phom mai chai khon Thai khrap.
I am not Thai.

เขาไม่ใช่ครูค่ะ
Khao mai chai khru kha.
He or she is not a teacher.

นี่ไม่ใช่ของผมครับ
Ni mai chai khong phom khrap.
This is not mine.

ไม่ใช่ร้านนี้ค่ะ
Mai chai ran ni kha.
It is not this shop.

The answer mai chai can also mean “No, that is not correct.”

Question:

คุณเป็นหมอใช่ไหมครับ
Khun pen mo chai mai khrap?
You are a doctor, right?

Answer:

ไม่ใช่ครับ
Mai chai khrap.
No, I am not.

This pattern is different from placing mai before an ordinary adjective.

Mai Chai Versus Mai + Adjective

Use mai chai when rejecting identity or classification.

เขาไม่ใช่คนไทย
Khao mai chai khon Thai.
He or she is not Thai.

Use mai directly before an adjective when rejecting a description.

เขาไม่สูง
Khao mai sung.
He or she is not tall.

Another comparison:

นี่ไม่ใช่กาแฟ
Ni mai chai kafae.
This is not coffee.

กาแฟไม่ร้อน
Kafae mai ron.
The coffee is not hot.

These patterns are important when building accurate negative sentences in Thai.

Saying “Do Not Have” With Mai Mi

The expression:

ไม่มี — mai mi — do not have, there is no

combines mai with mi, meaning “have” or “there is.”

Examples:

ผมไม่มีรถครับ
Phom mai mi rot khrap.
I do not have a car.

ร้านนี้ไม่มีห้องน้ำค่ะ
Ran ni mai mi hong nam kha.
This shop does not have a toilet.

ไม่มีปัญหาครับ
Mai mi panha khrap.
No problem.

ไม่มีเงินสดค่ะ
Mai mi ngoen sot kha.
I do not have cash.

วันนี้ไม่มีเวลา
Wan ni mai mi wela.
I do not have time today.

The subject may be omitted when the meaning is clear.

Asking Whether Something Is Available

The positive question pattern is:

มี…ไหม — mi…mai — is there, do you have

Examples:

มีห้องน้ำไหมครับ
Mi hong nam mai khrap?
Is there a toilet?

Negative answer:

ไม่มีครับ
Mai mi khrap.
No, there is not.

Another example:

มีอาหารมังสวิรัติไหมคะ
Mi ahaan mangsawirat mai kha?
Do you have vegetarian food?

ไม่มีค่ะ
Mai mi kha.
No, we do not.

This question-and-answer pair is useful in restaurants, hotels, shops, and transport situations.

Saying “Never” With Mai Khoei

The expression:

ไม่เคย — mai khoei — never, have never

appears before the main verb.

Examples:

ผมไม่เคยไปเชียงใหม่ครับ
Phom mai khoei pai Chiang Mai khrap.
I have never been to Chiang Mai.

ฉันไม่เคยกินอาหารนี้ค่ะ
Chan mai khoei kin ahaan ni kha.
I have never eaten this food.

เขาไม่เคยเรียนภาษาไทย
Khao mai khoei rian phasa Thai.
He or she has never studied Thai.

เราไม่เคยเจอกัน
Rao mai khoei choe kan.
We have never met.

The pattern is:

Subject + mai khoei + verb

This form is helpful when talking about life experiences.

Saying “No Longer” With Mai…Laeo

Thai can express “no longer” or “not anymore” using:

ไม่…แล้ว — mai…laeo

Examples:

ผมไม่อยู่ที่นั่นแล้วครับ
Phom mai yu thi nan laeo khrap.
I no longer live there.

เขาไม่ทำงานที่นี่แล้ว
Khao mai tham ngan thi ni laeo.
He or she does not work here anymore.

ฉันไม่กินกาแฟแล้วค่ะ
Chan mai kin kafae laeo kha.
I do not drink coffee anymore.

ร้านไม่เปิดแล้ว
Ran mai poet laeo.
The shop is no longer open.

The word laeo shows that the previous situation has changed.

Negative Commands With Ya

To tell someone not to do something, use:

อย่า — ya — do not, do not do that

The pattern is:

Ya + verb

Examples:

อย่าไปครับ
Ya pai khrap.
Do not go.

อย่าจับค่ะ
Ya chap kha.
Do not touch.

อย่าวิ่งครับ
Ya wing khrap.
Do not run.

อย่าลืมค่ะ
Ya luem kha.
Do not forget.

อย่าเปิดประตู
Ya poet pratu.
Do not open the door.

Using mai instead of ya does not create the same type of command. For direct negative instructions, ya is usually the correct word.

Polite Ways To Tell Someone Not To Do Something

A direct command can sound strong. Polite particles and softer phrases may help.

Examples:

อย่าจับนะครับ
Ya chap na khrap.
Please do not touch.

กรุณาอย่าสูบบุหรี่ค่ะ
Karuna ya sup buri kha.
Please do not smoke.

ไม่ต้องใส่น้ำตาลครับ
Mai tong sai namtan khrap.
There is no need to add sugar.

ไม่ต้องรอค่ะ
Mai tong ro kha.
You do not need to wait.

The expression:

ไม่ต้อง — mai tong — do not need to

is softer and different from ya, which directly tells someone not to perform an action.

Saying “Do Not Need To”

Use:

ไม่ต้อง — mai tong — do not need to, no need to

Examples:

ไม่ต้องห่วงครับ
Mai tong huang khrap.
Do not worry.
There is no need to worry.

ไม่ต้องมาพรุ่งนี้ค่ะ
Mai tong ma phrung ni kha.
You do not need to come tomorrow.

ไม่ต้องจ่ายครับ
Mai tong chai khrap.
You do not need to pay.

ไม่ต้องรีบค่ะ
Mai tong rip kha.
There is no need to hurry.

This is another useful pattern for negative sentences in Thai, especially when giving reassurance or explaining that something is unnecessary.

Negative Questions

A common question uses an ordinary positive sentence followed by mai.

คุณไม่ไปไหมครับ
Khun mai pai mai khrap?
Are you not going?

Although grammatically possible, this can feel confusing for beginners because the sentence contains both the negative word and the question particle.

It is often clearer to ask:

คุณจะไปไหมครับ
Khun cha pai mai khrap?
Will you go?

Then allow the listener to answer positively or negatively.

Another natural checking pattern is:

ไม่ชอบเหรอครับ
Mai chop roe khrap?
You do not like it?

Roe shows surprise or asks for confirmation.

Beginners can focus first on simple positive questions and negative answers before using more complicated negative questions.

Polite Particles In Negative Sentences

Male speakers commonly add:

ครับ — khrap

Female speakers commonly add:

ค่ะ — kha

Examples:

ผมไม่เข้าใจครับ
Phom mai khao jai khrap.
I do not understand.

ฉันยังไม่พร้อมค่ะ
Chan yang mai phrom kha.
I am not ready yet.

ไม่เอาครับ/ค่ะ
Mai ao khrap/kha.
No, thank you.

ไม่มีครับ/ค่ะ
Mai mi khrap/kha.
There is none.
I do not have it.

The polite particle does not change the grammar, but it makes negative sentences in Thai sound more appropriate in many everyday situations.

Subjects Can Be Omitted

Thai often omits pronouns when the subject is obvious.

Full sentence:

ผมไม่รู้ครับ
Phom mai ru khrap.
I do not know.

Natural shorter version:

ไม่รู้ครับ
Mai ru khrap.
I do not know.

Full sentence:

ฉันไม่เอาค่ะ
Chan mai ao kha.
I do not want it.

Shorter version:

ไม่เอาค่ะ
Mai ao kha.
No, thank you.

Beginners may include pronouns while learning the pattern, but shorter forms often sound more natural in real conversation.

Useful Negative Sentences For Everyday Life

ไม่เป็นไรครับ/ค่ะ
Mai pen rai khrap/kha.
It is okay.
Never mind.
No problem.

ไม่รู้ครับ/ค่ะ
Mai ru khrap/kha.
I do not know.

ไม่เข้าใจครับ/ค่ะ
Mai khao jai khrap/kha.
I do not understand.

ไม่เอาครับ/ค่ะ
Mai ao khrap/kha.
I do not want it.

ไม่เผ็ดครับ/ค่ะ
Mai phet khrap/kha.
Not spicy.

ไม่แพงครับ/ค่ะ
Mai phaeng khrap/kha.
Not expensive.

ไม่มีครับ/ค่ะ
Mai mi khrap/kha.
I do not have it.
There is none.

ยังไม่พร้อมครับ/ค่ะ
Yang mai phrom khrap/kha.
I am not ready yet.

ไปไม่ได้ครับ/ค่ะ
Pai mai dai khrap/kha.
I cannot go.

ไม่ใช่ครับ/ค่ะ
Mai chai khrap/kha.
No, that is not correct.

These short forms are among the most valuable negative sentences in Thai for beginners.

Common Beginner Mistakes

Placing Mai After The Verb

For a simple negative action, mai normally comes before the verb.

Correct:

ผมไม่ไป
Phom mai pai.
I am not going.

Confusing Mai With The Question Particle

ไม่ — mai means not.

ไหม — mai creates a yes-or-no question.

They have different Thai spellings and tones.

Using Mai Chai Before An Adjective

Use mai chai for identity or classification.

Use mai directly before an adjective.

Correct:

อาหารไม่เผ็ด
Ahaan mai phet.
The food is not spicy.

Confusing “Do Not” And “Cannot”

ไม่ไป — mai pai means do not go or am not going.

ไปไม่ได้ — pai mai dai means cannot go.

Using Mai For A Negative Command

Use ya to tell someone not to do something.

อย่าจับ
Ya chap.
Do not touch.

Translating English Word For Word

Thai may use a shorter pattern and omit pronouns or other words that English requires.

Avoiding these mistakes will make your negative sentences in Thai clearer and more natural.

A Simple Practice Method

Begin with a positive sentence:

ผมกินเนื้อ
Phom kin nuea.
I eat meat.

Make it negative:

ผมไม่กินเนื้อ
Phom mai kin nuea.
I do not eat meat.

Change it to “not yet”:

ผมยังไม่กินเนื้อ
Phom yang mai kin nuea.
I have not eaten meat yet.

Show inability:

ผมกินเนื้อไม่ได้
Phom kin nuea mai dai.
I cannot eat meat.

Show a past event that did not happen:

เมื่อวานผมไม่ได้กินเนื้อ
Muea wan phom mai dai kin nuea.
Yesterday, I did not eat meat.

Practising one sentence in several forms helps you see how the position of each negative expression changes the meaning.

Essential Negative Patterns To Remember

Mai + verb
Do not perform the action

Mai + adjective
Is not described that way

Yang mai + verb
Have not done it yet

Verb + mai dai
Cannot perform the action

Mai dai + verb
Did not perform the action

Mai chai + noun or identity
Is not that person or thing

Mai mi + noun
Do not have or there is no

Mai khoei + verb
Have never performed the action

Ya + verb
Do not do the action

Mai tong + verb
Do not need to perform the action

These patterns cover most beginner negative sentences in Thai.

👉 “Readers learning how to form negative sentences may also explore these useful Thai adverbs for everyday conversation to make their speaking more natural and precise.”

Conclusion

The most important word for making negative sentences in Thai is mai, meaning “not” or “do not.” It usually appears immediately before a verb or adjective.

Use mai + verb for simple negative actions, such as mai pai, meaning “not going.” Use mai + adjective for descriptions such as mai phet, meaning “not spicy.”

Use yang mai for “not yet,” mai mi for “do not have,” and mai chai for “is not” when rejecting an identity or category.

The position of mai dai changes its meaning. A verb followed by mai dai normally expresses inability, while mai dai before a verb often shows that a past action did not happen.

Use mai khoei to say “never,” ya to create a negative command, and mai tong to say that an action is unnecessary.

Thai verbs do not change when a sentence becomes negative. Subjects and pronouns may also be omitted when the meaning is clear.

Practise negative sentences in Thai by starting with a positive sentence and changing one part at a time. With a small set of reliable patterns, you can explain what you do not know, do not want, cannot do, have not finished, or do not need in many everyday situations.

FAQ

What Is The Main Negative Word In Thai?

The main negative word is ไม่ — mai, meaning “not” or “do not.” It usually appears before a verb or adjective.

How Do You Say “I Do Not Understand” In Thai?

Say ไม่เข้าใจ — mai khao jai. Male speakers may add khrap, while female speakers may add kha.

How Do You Say “Not Yet” In Thai?

Use ยังไม่ — yang mai before the verb, as in yang mai kin, meaning “have not eaten yet.”

What Is The Difference Between Mai Pai And Pai Mai Dai?

Mai pai means “not going,” while pai mai dai means “cannot go.”

How Do You Say “Is Not” In Thai?

Use ไม่ใช่ — mai chai when rejecting an identity or category, such as “This is not mine.”

How Do You Say “Do Not Have” In Thai?

Use ไม่มี — mai mi, as in mai mi ngoen sot, meaning “I do not have cash.”

How Do You Say “Never” In Thai?

Use ไม่เคย — mai khoei before the verb.

How Do You Tell Someone Not To Do Something?

Use อย่า — ya before the verb, as in ya chap, meaning “Do not touch.”

How Do You Say “Do Not Need To” In Thai?

Use ไม่ต้อง — mai tong before the verb, as in mai tong ro, meaning “You do not need to wait.”

Do Thai Verbs Change In Negative Sentences?

No. Thai verbs normally remain unchanged. A negative word or expression is added to create the required meaning.