frank.fan

well~guys,i'm a totally newer about houdini,i have a very strange problem when i learn the application.I don't know why or i'm not sure i touch which key ,just suddenly the timeline's around appear a yellow box，and then i can't control my houdini except the timeline,i can slide it, move,scale the key,but i only can do it,not more…so,who can help me?Thx(…forgive my poor english~~)