Te Reo Māori

Kia ora everyone. Just wanted to share a small win. I keep trying to remember to say "Kei te pai au" and it's finally starting to stick. I remember "Ka pai" as well. Just a small step, but it feels good to get a handle on some of the basics!

In the phrase “kei te pai au” from my knowledge of Hawaiian I understand that au is “i” and pai means good. But I don’t understand the usage of kei te