[huffmsa]

I don't support the argument here that Fluency == Knowledge of parts of speech.

I don't think of English as a formal structure except for when I'm editing a written document.

Fluency is the ability to carry on an uninterrupted conversation with another fluent speaker.

Immersion (true immersion, where you don't try to cheat) is the best way to become fluent.

You've gotta be Daniel Day Lewis.