you can't function on an empty stomach — you have to eat first
Antes de começarmos a mudança, vamos almoçar: saco vazio não para em pé.
Before we start the move, let's have lunch — you can't work on an empty stomach.
A well-known Brazilian proverb (ditado popular). Its origin is not documented; the only explanation offered is the transparent image behind it — a cloth or leather sack stands upright only when it's full, so the sack stands for the body that needs food to keep going.
Sources: Ciência Hoje das Crianças, Poder360.
Falando's Idiom Trainer teaches you to recognize idiom meanings and create sentences using them, so you can speak like a Brazilian.
