The word แย่ [yâe] is an adjective meaning “bad” or “terrible.” For example, “อากาศแย่” [aagàat yâe] bad weather, “รสชาติแย่” [rótchâat yâe] bad taste or “นิสัยแย่” [nísǎi yâe] bad attitude. However, when used as an adverb to intensify an adjective, it means “badly” or “terribly” as in “very” or “to a great degree.” However, we typically don’t use this word when we want to say “very.” As you may already know, we use the word “มาก [mâak].”
The colloquial idiom “[adj.] + แย่(เลย) [yâe (loei)]” is usually used in a response to someone’s statement, to speculate or make an assumption about the consequence that is likely to be true, of an action or a situation that happened, is happening or will happen. It’s similar to the use of the modal verb “must” in English. This expression is most commonly used when you want to show empathy for someone, but can also be used in other contexts. Look at the examples below for better understanding.
Examples
1.) A: ตอนนี้บ้านเราแอร์เสีย
[dtawn níi bâan rao air sǐa]
My air conditioner is broken now.
B: เหรอ ร้อนแย่ บ้านมีพัดลมไหม
[rǎw ráwn yâe, bâan mii pátlom mái]
Oh it is? It must be very hot (inside your house). Do you have a fan?
2.) A: ตอนเช้าเราหกล้มตอนวิ่งลงบันได
[dtawn cháao rao hòk lóm dtawn wîng long bandai]
This morning, I fell as I ran down the stairs.
B: เหรอ เจ็บแย่เลย
[rǎw, jèb yâe loei]
You did? That must have hurt a lot!
3.) A: สามีไม่ช่วยเราเลี้ยงลูกเลย
[sǎamii mâi chûai rao líang lûuk loei]
My husband doesn’t help me look after the kids.
B: เหนื่อยแย่ ว่างๆเดี๋ยวเราไปช่วย
[nèuai yâe, wâang wâang dǐao rao pai chûai]
You must be exhausted. I’ll help you look after them if I’m free.
4.) A:เมื่อวานรถน้ำมันหมดกลางทางด่วนตอนตีสอง
[mêua waan, rót námman mòt glaang taang dùan dtawn dtii sǎwng]
Yesterday, my car ran out of gas in the middle of the freeway at 2AM.
B: จริงเหรอ ลำบากแย่เลย แล้วทำยังไงอ่ะ
[jing rǎw, lam bàak yâe loei, léaw tam yang ngai à]
Really? It must have been hard for you. What did you do?
5.) A: เรากะจะใส่พริกสามเม็ด แต่ใส่ไปหก
[rao gà jà sài prík sǎam mét, dtàe sài pai hòk]
I was going to put three chilies, but ended up putting six.
B: โอ๊ย เผ็ดแย่เลย เราไม่กินแล้วได้ไหม
[óoi, pèt yâe loei, rao mâi gin léaw dâai mái]
Woah, it must be very spicy. Is it OK if I don’t eat it?
6.) A: ตอนไปหาหมอฟัน ต้องนั่งรอคิวตั้งสามชั่วโมงแน่ะ
[dtawn pai hǎa mǎw fan, dtâwng nâng raw queue dtâng sǎam chûa moong nàe]
When I went to see the dentist, I had to wait for three hours to be called.
B: เบื่อแย่เลย เขามีหนังสือพิมพ์ให้อ่านไหม
[beùa yâe loei, káo mii nángsěupim hâi àan mái]
You must have been so bored. Did they have newspapers for you to read?
7.) A: ปีหน้าเราจะไปเรียนต่ออังกฤษ กลับมาอีกทีสี่ปีหน้าเลย
[pii nâa rao ja pai rian dtàw angkrìt glàp maa ìik tii sìi pii nâa loei]
I’m going to study in England. I’ll come back in four years.
B: โห นานจัง คิดถึงแย่เลย
[hǒ, naan jang, kíd těung yâe loei]
Wow, that’s such a long time. I’m going to miss you so badly.
8.) A: ฉันสอบเข้าไม่ได้ อดเรียนโรงเรียนที่แม่อยากให้เข้าเลย
[chán sàwp kâo mâi dâai, òd rian rong rian tîi mâe yàak hâi kâo loei]
I failed the entrance exam. I won’t get to study at the school my mom wants me to.
B: น่าเสียดายจัง แม่แกเสียใจแย่เลยดิ
[nâa sǐa daai jang, mâe gae sǐa jai yâe loei dì]
What a shame. Your mother must be very sad.
Remark: note that as in the last two examples, you can use the expression “[adj.] + แย่(เลย) [yâe (loei)]” to talk about your own feelings as well as a third person’s. In the first case, as you’re talking about yourself, you don’t see the word “must” in the translation.

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