Yesterday I started Spanish (and practiced German, Dutch and Japanese). So do I know it yet? Actually, yes.
I spoke yesterday of letting Spanish wash over me, and of being activated. A better analogy is of rain falling in the desert (‘the rain in Spain stays mainly on the plain’). By listening to Spanish it’s like turning on the sprinkler. Thereby every aspect of the language begins to grow.
On the other hand, conventional language instruction drenches a small area of selected vocabulary and grammar-point-of-the-day with a bucket of water—which then runs off and evaporates ‘mainly’ without lasting effect.