keep somebody posted 
spoken
  to regularly tell someone the most recent news about something

keep somebody posted on 
e.g.,I'll keep you posted on his progress.

let go ول کن
 to stop holding something or someone
e.g., Let go! You're hurting me

eat your heart out
 used to say, especially humorously, that something is very good
That's a great drawing. Pablo Picasso eat your heart out