理直气壮

lǐ zhí qì zhuàng

confident because you are in the right

Character by character

理lǐ
reason

直zhí
straight

气qì
spirit

壮zhuàng
strong

他理直气壮地提出了自己的要求。

He boldly stated his demands.

Tone: neutral.

Can be ironic when someone is brazen though wrong: 他还理直气壮的.

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