1. "My mom has been harping on me for getting a job during summer. It's driving me nuts!"2. "He was always harping on the importance of taking vitamin supplements."3. Brother: If you are home when mom comes home, she'll keep nagging you about cleaning your room, doing your homework. Let's sneak out.
 to harp on to nag somebody about something nag 是嘮叨跟囉嗦的貼切的說法之一。 P.S. 正確的中文是嘮叨，而不是撈叨。