As I start to get into my Russian I run into so many things that are impossible to learn and remember the first time around. An example is the names of the numbers in Russian.
The system I am using is “teach yourself Russian” . “Teach yourself” claims to have sold 40 million of their books on learning different languages. One of their instructions is to make sure you master one chapter before going on to the next.
What nonsense! To be good a language learning you have to let things go by you. I cannot count to ten, and then to one hundred and then to ten thousand, and then identify telephone numbers etc. in Russian. I cannot remember the names of the days of the week. It does not matter. Gradually, as I need this things, and after seeing and hearing them often enough, I will learn them. I know I will. So I let them go. I advance to chapter 8 when I still only know parts of chaper 4. Then I will go back and do chapter 4 again, many times.
You have to let things go. Eventually it all starts to make sense. When it does you start to use the language. Before that, you just let it flow by you, picking up what you can, confident in the knowledge that you will learn if you stay with it.
Now of course if I had The Linguist system in Russian at least I would have a better grasp of new vocabulary and more interesting content to learn from.