have big shoes to fill
US /hæv bɪɡ ʃuːz tu fɪl/
UK /hæv bɪɡ ʃuːz tu fɪl/

1.
大きな役割を担う, 前任者の功績に匹敵する
to have a difficult job to do because the person who did it before you was very good or successful
:
•
The new CEO will have big shoes to fill after the legendary founder retired.
伝説的な創設者が引退した後、新しいCEOは大きな役割を担うことになるだろう。
•
She's a brilliant teacher, and whoever replaces her will certainly have big shoes to fill.
彼女は素晴らしい教師なので、後任の人は間違いなく大きな役割を担うことになるだろう。