It’s a truth universally acknowledged that language immersion works. If you drop somebody into the French countryside to be a scullery maid for a family who talks a lot, they will probably be fluent in French within the next few years. It wouldn’t work if you know no French language and are barely exposed to real French conversations, but if you’ve got a couple of hundred words in your repertoire and are actively engaging in conversation whether you understand it or not, you might be dreaming in French sooner than you’d think. 

The hard part about language immersion is the feeling of inadequacy and exclusion. It’s not easy to never really hear your native language and constantly try to keep up with speakers of a foreign language who constantly talk fast and use slang. One teenager whose parents were trying to help him with language immersion felt this exact frustration, leading to a big family fight.