El tercer infinitivo se forma al tomar la raíz del verbo con su consonante en la forma fuerte y después añadir -ma/-mä, seguido por la declinación de caso. The third infinitive is formed by taking the verb stem with its consonant in the strong form, then adding -ma/-mä,...
An accident almost happened, and afterwards somebody said: キキがいけないんだよ! I have found it translated as "It is your fault!" 1.Is the translation correct? 2. Is いけない a negative verb or is it the adjective いけない?