Why Do Forests Act Like Giant Lungs?

Forests are like giant lungs for the Earth. Just like humans breathe in oxygen and breathe out carbon dioxide, trees do something similar, they take in carbon dioxide, which is a type of gas we humans mostly breathe out, and give off oxygen, the one we need to breathe in. When there are more trees, it means more breathing happening, so the Earth gets more fresh air, and we get fewer bad gases.