Just remember these ways of saying, because these are what the native speakers are using.
Language is nothing but a habit... as long as you could make good communications with native speakers..... you would definitely be disappointed if asking chinese pass-by how much grammer he or she knows...
Do not focus too much on grammers, especially on the earlier stage of learning. There are many people unschooled, they cannot read and write, but speak fluently....
Of course, except you want to be an expert in that language and culture... that'll be another case.