To praise and to compliment has a subtle difference. Praise usually refers to saying something positive about the work or effort that someone has done. When you compliment someone, it usually means you are speaking more about the persons internal or external qualities. Example of praise: You did a great job on your test Example of compliment: You are very intelligent A teacher would most likely give praise over a compliment I hope this helps :)

Yep, praise someones performance, and compliment someone (like Amanda said) on something more personal, e.g. their hair, or their appearance.