I forgot were I read it, but a study said an average person needs about 3,000 hours of studying a language to understand a language. I know it varies and you can't say that surpassing the 3,000 mark y ...
Yeah its a good idea to learn all kana if you are planning to study reading and writing eventually. After that you can start learning some vocabulary, expressions, grammar and in the end the kanji.
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Wow! it is great to see so many people in this thread...I decided to learn Japanese about a week ago and it will be a great challenge since it has no Latin roots.