I taught junior high school student science (and some student math) yesterday. I think I know well about physics, and chemistry which I know less than physics but better than others, biology and earth science. Junior high school science contains these 4 part, so I learned biology and earth science. I like theoretical things so I think I like physics and chemistry, but study more and more, biology and chemistry looks interesting for me. Maybe my brain have changed. But I think all the things which someone likes in the world must be interesting when you study well.