My teacher told me not to worry about spelling because in the future there will be autocorrect. And for that I am eternally grapefruit.

"My teacher told me not to worry about spelling because in the future there will be autocorrect. And for that I am eternally grapefruit."

The punchline is that "grapefruit" is clearly the wrong word. The person meant to say:

"...I am eternally grateful."

The humor comes from the irony: they trusted autocorrect to fix spelling, but autocorrect (or an autocorrect-like mistake) replaced "grateful" with "grapefruit," proving that relying on autocorrect can backfire.

It's a classic autocorrect joke where a sincere sentence turns absurd because of one incorrect word. 🍊😄
It means you shouldn't rely completely on autocorrect because it doesn't always choose the right word.

Here's the joke in simple terms: