심사숙고 give (something) a lot of thought

A : I've decided to go abroad to study.
     나 유학 가기로 결심했어.

B : When did you decide that? Aren't you being a little too hasty?
     언제 그런 결정을 내린 거야? 너무 성급한 거 아니야?

A : No, I've made up my mind after giving it a lot of thought? 
     아니야. 심사숙고 끝에 내린 결정이야. 
     I think it's time for me to learn as much as I can, to invest in myself more.
     지금은 많이 배우고, 나 자신에게 더 많이 투자할 시간인 것 같아.

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