青云翻译

For reasons known to all, he was unable to attend on behalf of the school speech contest.

For well-known reasons, he failed to represent the school in the speech contest.

Stemming from the well known reason, he has not been able to attend this oratorical contest on behalf of the school.

For reasons known, he was unable to participate in this meeting on behalf of the School Speech Contest.

For well-known reasons, he failed to represent the school in the speech contest.