It absorbed the carbon dioxide that the humans breathed out and replenished the air with oxygen.
(It; absorbed; the carbon dioxide that the humans breathed out and replenished the air with oxygen) (the carbon dioxide; breathed out; the humans) (the humans; replenished; the air; with oxygen)
It the carbon dioxide the humans
absorbed breathed out replenished
the carbon dioxide that the humans breathed out and replenished the air with oxygen
the humans
the air with oxygen