How to Ask "Why" in Japanese

"YUU ASAKURA: I'd like to add some more questions using "why". In Japanese, there are several ways to use the word "Why" The first one is "Naze," we learned already. And then we also use the word "Doushite." It has a--the original meaning is--of it in English is "How come?" Like, "How did it happen?" That's the feeling to it. So, you can use "Naze" or "Doushite" to demand an explanation, how it happened. So, we can use "Naze, Doushite" by itself, or you can add the sentence following these words, right after it. So, let's ask "Naze--Why are you-why are you busy? Do you remember you are busy?" "Yes. Anata wa ishogashii," right? So, if you make a yes or no question with are you busy, "Anata wa ishogashii desu ka?" Right. So, you put the word "Naze or Doushite" in front of it. "Naze anata wa ishogashii desu ka?" or you can use this one, "Doushite anata wa ishogashii desu ka?" That's very simple. So let's practice with--we use the--busy, so let's use the word free, "Hima." Okay. So, let's ask, "Why are you free? It's week day, why are you free?" How do you say it? Yes. "Naze anata wa hima desu ka?" That's very good."