YOU SAID:
Why do I think I need one?
INTO JAPANESE
なぜ私は 1 つを必要と思いますか。
BACK INTO ENGLISH
Why do I need one?
INTO JAPANESE
なぜ必要ですか。
BACK INTO ENGLISH
Why is it necessary?
INTO JAPANESE
なぜ その必要が?
BACK INTO ENGLISH
Why is it necessary?
That didn't even make that much sense in English.