먼저 가 금방 따라 갈게, 불쑥 찾아가다, 놀림감이 되게 하다, 숙연하게 하다.

Go ahead guys, I'll catch up.

(먼저 가 얘들아, 금방 따라 갈게)

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Is it fine for you to come barging into my school and make a complete fool out of me?

(네가 우리 학교 갑자기 불쑥 찾아와서 내가 놀림감이 되게 하는 건/망신 주는건 괜찮은 거야?)

to barge into something : 불쑥 찾아가다

to make a fool (out) of ~: 놀림감이 되게 하다, 망신을 즈다.

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don't tell me how to talk to my father when you are the same way.

==> 너희들도 같은 처지면서 내가 아버지한테 어떻게 말해야 하는지 설교하지마. 

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sober: (형용사) 술에 취하지 않은, 숙연한(차분한)

        (동사) 숙연하게 하다

not ​drunk or ​affected by ​alcohol:Are you sober enough to ​drive, Jim?I'd had no ​wine all ​evening so I was ​stone ​cold (= ​completely)sober.
​serious and ​calm:In ​fact the ​whole ​wedding was a sober ​affair - no ​dancing, just ​people ​standing around in ​groups ​chatting ​politely.Anthony was in a very sober ​mood - I ​scarcely ​heard him ​laugh all ​night.
to ​become more ​calm and ​serious, or to make someone do this:News of the ​tragedy sobered us.

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Buoyed by their new hopes,

==> 새로운 희망에 부풀어올라서(분사구문)