偉(えら)そうself-important, important-looking, proud

先輩(せんぱい)：「おい、先輩(せんぱい)に偉(えら)そうな顔(かお)をするな！」

Senior: "Hey, don't put on a self-important face at me!" {self-important, important-looking, proud}

同僚(どうりょう)に偉(えら)そうな態度(たいど)をとる社員(しゃいん)は嫌(きら)われています。

Employees who act self-important towards their colleagues are disliked. {self-important, important-looking, proud}

上司(じょうし)に偉(えら)そうな口(くち)をきいたら上司(じょうし)から叱(しか)られてしまった。

I was scolded by my boss after I spoke to him in a self-important manner. {self-important, important-looking, proud}

兄(あに)が弟(おとうと)に：「おい、兄(あに)に向(む)かって偉(えら)そうな事(こと)を言(い)うなってば！殴(なぐ)るぞ！」

My brother said to his younger brother: "Hey, stop saying self-important things to me! I'll punch you!" {self-important, important-looking, proud}

偉(えら)そうにふんぞりかえっている上司(じょうし)が憎(にく)いのなんのって…。顔(かお)を見(み)るだけで吐(は)き気(け)がする！

I absolutely loathe my boss who's always lounging around acting all self-important... Just seeing his face makes me feel nauseous! {self-important, important-looking, proud}