哪里哪里。(Nǎlǐ nǎlǐ.)(politely responding to thanks or praise given) Not at all.

Explanation

当有人感谢或者夸赞自己时,人们说“哪里哪里。”表示谦虚和礼貌,意思是“不是这样,没有您说的那么好”,或者表示委婉地否定。
People respond “哪里哪里”(Nǎlǐ nǎlǐ.) when they are thanked or praised by others in order to show their modesty and politeness. It means “it’s not that good as you said” or it can be a polite denial either.

Words:

宽敞kuānchǎnɡ:spacious;
明亮mínɡliànɡ:bright.

Sentences

1、Jiǎ: Nǐmen zuò de fēicháng bàng!
甲:你们做得非常棒!
A: Well done! You are excellent.

Yǐ: Nǎlǐ nǎlǐ.
乙:哪里哪里。
B: Thank you. You are over flattering us.

2、 Jiǎ: Nǐ de xīnfāng kuānchǎng míngliàng, zhùzhe yídìng huì hěn shūfu.
甲:你的新房宽敞明亮,住着一定会很舒服。
A: Your new house is so spacious and bright, and it must be very comfortable to live in.

Yǐ: Nǎlǐ nǎlǐ,wǒ juéde wǔ ge rén zhù háishì xiǎo le diǎnr.
哪里哪里,我觉得五个人住还是小了点儿。
B: Thanks. But I don’t think it is big enough for five persons.

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