1、Then the skylark flew up and alighted upon the back of the eagle and began to pick at his feathers.
于是云雀飛起來，撲在鷹的背脊上，啄起鷹的羽毛來了。

2、There is no need to pick at him all day long. He's a child after all.
不要老是對他嘮嘮叨叨，他畢竟還是個孩子嘛!

3、Fish pick at the urchins, which feed on bits of algae.
魚類吃海膽，海膽以小塊的藻類為食。

pick at翻譯