Simplify the following text for a Grade 11 native English-speaking person.
Original: Same-sex marriage ( also known as gay marriage ) is a term for a relationship in which two people of the same sex live together as a family in a governmentally , socially , or religiously recognized marriage .
Simplified: Same-sex marriage ( also called gay marriage ) is a legally or socially recognized marriage between two persons of the same biological sex or social gender .