It's gotta be the particles
The particles are the really difficult thing for me to get right. Even Japanese kids get them wrong or more commonly just leave them out when speaking.
In fact a Japanese friend said that in conversation, if you're unsure, just don't bother - your listeners will get your jist and it's painful waiting around for someone to pick out the right particle when 90% of the time you can work out what someone is saying without them.
With writing though, the particles have to be right and it's definitely more noticeable if you get them wrong....
Don't worry, we are the same.
Did you guys know there are some aho native Japanese who still can't spell katakana "n" and "so" or "tsu" and ""shi" correctly?
「ン」(n)
「ソ」(so)
「ツ」(tsu)
「シ」(shi)
You don't mess them up when you type on keyboard, but what about when handwriting?
P.S. For the people who don't know what aho means:
aho=baka=stupid:blush: