To keep something on the down-low means to keep information secret.

“To keep something on the down-low”是指对信息保密。

'cause if you don't keep something on your plate, food, you'll get another time food.

因为如果你不在盘子里放点东西， 食物，你会得到另一次食物。

An " elastic band" is something that stretches and we use those to keep something on our head like a mask.

“松紧带”是一种可以拉伸的东西，我们用它来像面具一样把东西戴在头上。