I insist on this point. 我强调这一点
He insists on his innocence.=He insists (on it) that he is innocent. 他坚持自己是无罪的
He insists on going to the movies. 他非要去看电影不可
She insisted (on it) that you (should) be invited to the party. 她一定要邀请你去参加聚会
I'll have another glass if you insist. 既然你执意劝酒,我就再喝一杯.