I thought when you get a type one verb ending with "ku" you replace it with ita. For example Kaku (to write) goes to Kaita. So I'm guessing Iku is an exception, does this happen with other verbs too ? ...
"It seems there is none" is なさそう, which escapes the usual rule for 形容詞 (イ-adjectives), which says "drop the い and add そう". Is there a historical explanation for this exception? And does it have ...