What is a big green fruit with pink inside called?

The most likely answer is a watermelon. It's a large, green fruit with a juicy, pink flesh.

However, there are other possibilities, though less common:

* Green-skinned cantaloupe: Some varieties of cantaloupe have a greenish rind.

* Honeydew melon: While not technically pink, the flesh of honeydew can have a slightly salmon-pink hue.

To be sure, you'd need more information about the fruit's size, shape, and texture.