This phrase expresses possibility or probability, meaning 'might do', 'perhaps', or 'it's possible that'. It indicates that something could happen or could be true, but it's not certain. Connect it to the plain form of verbs, adjectives, and nouns (add だ).

何かが起こるかもしれない、そうかもしれないという可能性を表します。普通形に接続します。