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to handle; to manage; to deal with; to work with; to have experience with
to rear; to look after
彼は若い頃から数多くの建築設計を手がけてきた。
He has been involved in numerous architectural designs since his youth.
この映画を手がけた監督は新人だと聞いた。
I heard that the director who worked on this film is a newcomer.
初めて海外案件を手がけることになり緊張している。
I am nervous about handling an overseas project for the first time.