I'm a Vietnamese-American, born/raised in the US, who is about to make a move to Vn. Vietnamese was my first language, but since i grew up in the U.S. primarily around non-Vn people, I only speak it now at a very basic/elementary level. I don't know how to read/write.
Has anybody here in a similar situation as me been able to pick up speaking Vietnamese much more fluently (i.e., >professional level) after living in Vietnam for some time? Or do you know someone who has? If so, about how long did it take you or your friend?