Japanese - Ask questions thread

Basically if you have a question about the language, ask it and fellow 4channers might see it and answer it for you.

To start it off. When an animate object (iru) dies, is it considered inanimate(aru)?

Question:
What kinds of "keiyoushi" use "ga" and what kinds of them use "ni"?
Examples:zou wa hana "ga" nagai
         sensei wa rekishi "ni" kuwashii
         sensei wa gakusei "ni" kibishii
Am I correct?