Fluency
As I see it there are a few levels of fluency in a new language.
Level 1) You can get around and make what you want to happen, happen. e.g. You can buy a train ticket or order food or ask for directions and understand the conversation.
Level 2) You can make small talk. e.g. You hang out with native speakers and can participate in varied conversation. You may not necessarily understand every word, and jokes/technical details might go over your head, but it's not a huge stretch to involve yourself in convos about music, movies, and life.
Level 3) You can flirt/date/etc. e.g. You can talk to a girl (or guy), get her number, make plans, so on and so forth. :) You still fumble for words, but you can make things happen.
Level 4) You can hold a conversation that's more than just small talk. e.g. A philosophical discussion.
Level 5) Not much else matters more than #3 so I'll stop. ;)
