What does nani sundayo, mean in Japanese?

“What the heck are you doing?!”
“What’d you do that for?!”

Hope this helps.

Source(s): Japanese is my native language.

nani is what kore is this. the object ur talking about has to be closer to the speaker kare is him, you can use it when introducing or when talking about your boyfriend.

What are you doing!

I think it means- “What are you doing?”