Thread:Uncle Nimu-Dash/@comment-29450877-20160901010624/@comment-27347196-20160915045623

CherryMei wrote: don't care still using question marks I told him I don't speak Japanese too well before he gets idea I'm native speaker or something in here and he responded that he already knew based on silly mistake I made when I asked him question

Your Japanese is good as I said.

And yes it is not completely incorrect but it is kinda dumb. It is like asking question of "What is your name??" or "How are you??" with double question marks. Not incorrect but it is beyond unnecessary if there is 'ka'.

Therefor it is not hard to guess when you should use/not question mark. If your sentence ends with 'ka' then don't if it doesn't and it is informal then you can use question mark as optional option. Simple really.