do double duty
成語所屬單字duty
do double duty — 慣用語
1. to serve two purposes or functions at the same time.
1.慣用語
釋義
一物兩用；身兼二職
to serve two purposes or functions at the same time.
例句
The storage box does double duty as a coffee table in the small apartment.
Amihan's laptop bag does double duty as her overnight bag for short work trips.