Let's learn some Chinese Colloquial Phrases. Today, we're going to learn Chinese Colloquial Phrases—“不敢当”. 

不敢当（bù ɡǎn dānɡ）。
I'm flattered.

用法说明

“不敢当”是一种谦虚的说法， 当别人向你表达称赞、信任的时候，你可以用“不敢当”来谦虚地表示自己承担不起这样的称赞、信任。中国人在受到别人称赞时往往要表现出谦虚的态度。

"不敢当" is a kind of euphemism. When someone praises you or expresses his/her trust in you, you can use this as a polite way by indicating that you are not worthy of such compliments. Chinese people are used to show their modesty when they are receiving compliments from others.

例句
Example

1.甲：你是我见过的最聪明的人！
Jiă: Nǐ shì wǒ jiàn ɡuo de zuì cōnɡmínɡ de rén!
1.A: You are the smartest person I've ever seen.

乙：不敢当。
Yǐ: Bù ɡǎn dānɡ.
B: I'm flattered.

2.甲：只有你能完成这个任务。
Jiă: Zhǐyǒu nǐ nénɡ wánchénɡ zhèɡe rènwù.
2.A: You are the only one who can accomplish this task.

乙：不敢当，我会尽力的。
Yǐ: Bù ɡǎn dānɡ, wǒ huì jìnlì de.
B: I don't deserve this, but I'll do my best.

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