To sleep together or live in sexual intimacy without being married.
同居：未婚而睡在一起或有亲密性行为而住在一起
To live, room, or stay at a place
同住：生活、居住或停留在某处
I'm shacking up with my cousin till I find a place of my own.直到我找到自己的房子我将与表弟住在一起
I'm shacking up with my cousin till I find a place of my own.
直到我找到自己的房子我将与表弟住在一起