他受邀在大学毕业典礼上发表演讲。

He was invited to ___speak at the university's graduation ceremony.

我谨代表组委会，邀请您在我们的年度盛会上发表讲话。

On behalf of the organising committee, I'd like to ask you to ___speak at our annual gala.

能在如此尊贵的听众面前演讲，我深感荣幸。

It's a great honour to ___speak before such a distinguished audience.