Here's a breakdown:
* Tena koe: This is a polite greeting, similar to "Hello" or "Good morning."
* ngā mihi nui ki a koe: This means "best wishes to you" or "happy birthday to you."
* i tēnei rā whānau: This means "on this birthday."
You can also use a simpler version: "Ngā mihi nui i tēnei rā whānau!" This is a more direct translation of "Happy Birthday."
It's important to remember that Māori is a living language, and there are different ways to express this phrase. This translation is one common way to say "Happy Birthday" in Māori.