When to use 漢字、カタカナ、ひらがな I know one basic rule - カタカナis for words from foreign countries and 擬声語/擬態語. ひらがな for 固有日本語. 漢字 is used for a more formal case. I understand some changes for the purpose of good design. But the more I get to know Japanese, the more confused I get. １） ポイ捨てor ぽいすて or ぽい捨て　禁止　 ２）泣き面に蜂　or なきつらに蜂　 ３）いちかばちか or　いちか八か or　一か八か ３－１）いちからじゅうまで　or いちから十まで or　一から十まで Is it okay to use かんじ whenever there's a 漢字 for that word like the last example above? Which one is commonly used? Would you tell me the reason why? Thanks!!