Learn English: Galaxies Have Special Ways to Stay Healthy (easy)

Galaxies are like big groups of stars, and they are always making new stars from gas.

But if they make too many stars too quickly, they could run out of gas and die.

Luckily, galaxies have a special trick! They have a giant black hole at their center that helps control the gas.

This black hole acts like a heart, sending out energy that helps the galaxy stay healthy and make new stars for a long time.