"I hope you had a fun time with friends" => 친구들하고 재미있게 놀았길 바라. But that is a rather literal translation, and 바라(hope) sounds too serious for the occasion. In real life, people just say 친구들하고 재미있게 놀았지? (Did you have a fun time with friends?). It is in a question form, but is more like "I expect/know you had a fun time ..." than asking a question in earnest.