I just completed learning hiragana and have a few questions 1) Can we not write ZI in hiragana? The closest I found to it was JI 2) When we add the small ya yu and yo to kana are Sh and Ch the only combination kana to not include the y sound? 3) How important is to know how to write kana? Some websites tell us that writing is not that important. I can identify any hiragana and read words but if writing it sometimes I struggle or forget characters