"ITS" and "IT'S"

"Its" shows possession. "It's" is a contraction for "it is" or "it has." Ex.: The dog wagged its tail. It's a lovely day outside.

"PRINCIPAL" and "PRINCIPLE"

"Principal" refers to a person in a position of authority or the primary part of something. "Principle" means a fundamental rule or belief. Ex.: The school principal addressed the students. The principal reason for our success is teamwork. Honesty is an important principle to uphold.