What it means
ようか〜まいか presents two alternatives: doing something and not doing it. It is used when the speaker is undecided, considering a choice, or describing someone’s hesitation. The first verb uses the volitional form, while the second uses the dictionary form followed by まいか. The construction often refers to the speaker’s own decision, but it can also describe another person’s uncertainty when the context makes the subject clear.
Usage note
ようか〜まいか is not itself a separate polite ending. To make the full sentence polite, change the surrounding predicate, while leaving the construction unchanged. Do not confuse it with かどうか, which asks whether something is the case rather than presenting the alternatives of doing and not doing an action.
How to use it
参加しようか参加するまいか、まだ決めていません。
I still have not decided whether to participate or not.
参加しようか参加するまいか、まだ決めていない。
I still have not decided whether to participate or not.
