I’ve been teaching Japanese language for a long time, then I recently realized something about the number how many text books you have.
It seems that related with how you speak Japanese well.
less or more?
From my teaching experiences, the students who don’t have much text books can improve Japanese well. On the other hand, It’s difficult to reach a particular level for the students who have a lot of text books.
I’m not sure, but I think that learning foreign language is so hard for brain. You have to use lot of energies for your mental and brain also.
Then, It is difficult to remember something new from multiple tools.
If you use one book, then your brain could concentrate on memorizing smoothly.
It’s way better to memorize about one thing 100% correctly than memorizing multiple things uncertainly.
I recommend “minna-no-nihongo”
It’s all okay what kind of book you use.
You should choose the one you like.
But if you are struggling with selecting nice one, I recommend “みんなの日本語 minna no nihongo”. This book is written by all Japanese. So, before you buy this one you should study Japanese alphabet which is called ひらがな hiragana, カタカナ katakana.
After that, you can learn Japanese from only this book with a teacher. I guess you need a teacher with this book. Because It is hard to understand the grammar point without a teacher.
If you couldn’t find a teacher, or want to study yourself, then the book below is good. You can learn with translations and explanations about grammar in English.
If you are an advanced levels of Japanese learner, you can buy any books you want.
if you are a beginner, Please focus on one book first.