"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.
"DISCREET" and "DISCRETE"
"Discreet" means careful or unobtrusive. "Discrete" means separate or distinct. Ex.: She was discreet about her personal life. The project was divided into discrete tasks.
