1. Use "raise" when a person moves something upward
2. Use "rise" when something moves upward on its own. Also, use "rise" when a person gets up from sitting or lying down.
Examples:
1a. Students raise their hands before speaking in class.
1b. Weightlifters raise barbells (weights) over their heads.
2a. The sun rises in the east.
2b. Hot air rises.
2c. People rise after they pray.
