what kind of, what sort of
どんな
why, for what reason, how
どうして
how, in what way, by what means
どうやって
subject marker/ identifier particle
が
but, however
が
there is, is (non living things)
がある
there is; to be; is (living things)
がいる
to want something
(が) 欲しい = ほしい
had better; it would be better to; should
方がいい = ほうがいい
i-adjective to adverb
暖かい = あたたかい -> 暖かく
i-adjective when conjugated
美味しい = おいしい -> おいしく(ない)