Explanation
Expresses 'whether or not', 'no matter if something happens or not'.
Formation
Verb-volitional form + が + Verb-negative volitional form + が
Detailed explanation
Verbようが Verbるまいが indicates that whatever happens—whether the action is done or not—the outcome remains unchanged or the speaker's stance remains the same.
Examples
彼が来ようが来るまいが、パーティーは始まります。
Kare ga koyou ga kurumai ga, paatii wa hajimarimasu.
Whether he comes or not, the party will start.
勉強しようがしまいが、テストの結果は変わらない。
Benkyou shiyou ga shimai ga, tesuto no kekka wa kawaranai.
Whether you study or not, the test results won't change.
雨が降ろうが降るまいが、ピクニックに行きます。
Ame ga furou ga furumai ga, pikunikku ni ikimasu.
Whether it rains or not, we're going on a picnic.
暑かろうが寒かろうが、毎日ジョギングします。
Atsukarou ga samukarou ga, mainichi jogingu shimasu.
Whether it's hot or cold, I jog every day.
Practice
Grammar content sourced from hanabira.org.