The interjection 哎哟
An interjection (感叹词) is a word or expression that occurs as an utterance on its own and expresses a spontaneous feeling or reaction. It expresses feelings and emotions but does not name them. It is usually placed at the beginning of a sentence.
The interjection 哎哟 
has several functions. It is translated as «ouch», «wow» or «oh». It expresses:
1) pain, grief, annoyance and regret.
has several functions. It is translated as «ouch», «wow» or «oh». It expresses:
1) pain, grief, annoyance and regret.Examples
哎哟，好痛苦！
Oh, how painful!
āiyō, hǎo tòngkǔ
哎哟，多疼了！
Ouch, what a pain!
āiyō, duō téng le
哎哟，太遗憾了！
Oh, what a pity!
āiyō, tài yíhàn le
2) sarcasm.
Examples
哎哟，你太聪明！
Oh, how smart you are!
āiyō, nǐ tài cōngmíng
哎哟，你怎么又来了？已经不生气了？
Wow! Why did you come again? Are you not angry anymore?
āiyō, nǐ zěnme yòu lái le? yǐjīng bù shēngqì le
哎哟！看这是谁呀？
Oh, look who it is!
āiyō, kàn zhè shì shéi ya
3) shock and wonder.
Examples
哎哟！我忘了给你买礼物了！
Oh, I forgot to buy you a present!
āiyō! wǒ wàng le gěi nǐ mǎi lǐwù le
哎哟，天气预报说明天白天35度！
Oh, according to the forecast, it will be +35C tomorrow afternoon!
āiyō, tiānqì yùbào shuō míngtiān báitiān sānshíwǔ dù
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