●be/go/keep ˈon at sb ( be ˈat sb) (informal, especially BrE) to try to persuade sb to do sth by talking about it very often and in an annoying way反复劝说；不断纠缠◆I’ve been on at my husband to go to the doctor, but he won’t. 我再三规劝我丈夫去看医生，可他就是不去。SYNnag sb[v + adv + prep][v + prep]