I might be a little biased to read this article and say this, but yes, vocabulary seems to be everything.
The more words you know and the harder they are, the easier it gets to learn new words. Simple as that. And grammar comes by accident.
Memorization of vocabulary in context, with the aid of tons of audio is the key. End of story.
Japanese verbs 3 「行っている」の意味
1 day ago