prep with reference to (sb/sth); concerning 对于(某人[某事物]); 关于; 至于 *She said nothing regarding your request. 她对你的要求只字不提.
regarding
朗文当代英英词典(第4版)
prep formal a word used especially in letters or speeches to introduce the subject you are writing or talking about = concerning, with regard to with regard to Regarding your recent inquiry, I have enclosed a copy of our new brochure.