Life is a singular noun. It only refers to one subject. (ex. "I have a life." Subject: yourself.) Lives is a plural noun. It refers refers to more than one subject or a group. (ex. "Save the lives of the animals." Subjects: Animal like dogs, cats, etc.)

Life is a singular noun. It refers to a single subject or person. Ex. I have a happy life with my wife and daughter. Lives is a plural noun. It refers to two or more subject. Ex. Thier lives was threathened by the strong typhoon.

The word ''LIFE'' is noun .The word ''LIVE'' or "LIVES" ( 3rd form of verb) is verb. All difference in this!!! Good luck!!!!