Okay, kiddo! So, imagine there are some people who really care about the environment and want to protect it. They're called the Greens. And there are some other people who really care about things like fairness and equality for everyone. They're called the Left.
Now, sometimes these Greens and Left people work together because they have some things in common. For example, they might both think that big corporations have too much power and influence in the world. So, they might team up to try to make laws or policies that help regular people more than big companies.
When the Greens and Left work together like this, we call it a Greens and Left alliance. It's like they're joining forces to try to make the world a better place for everyone. Sometimes, these alliances happen in politics, which is when we vote for people to make decisions for us.
Does that make sense, kiddo?