pick at something
phrasal verb with pick verb uk/pɪk/ us/pɪk/
disapproving
（因没胃口或不高兴而）一点一点地吃，挑挑拣拣地吃
to eat only a small amount of your food, showing no interest or enjoyment while you eat it
Charles picked at his food in a bored fashion. 查尔斯吃饭挑挑拣拣的，一点胃口也没有。
See also: picky