I was bobbing my head, so maybe I better bob my head again and sure enough another piece of corn comes.

我一直在摇头晃脑,那我最好继续摇头晃脑,这样的话我就能再得到一粒谷粒

耶鲁公开课 - 金融市场课程节选

You saw that in the way he stood bobbing his head, always looking down, nodding like a young boxer to instructions to make you think he was listening to every word, throwing in a thousand "yes"es and "that's right."

你看他站着摇头晃脑的样子，总是朝下看，像年轻的拳击手听指令时一样,那样晃着脑袋，好让你觉得他在听你说的每个字，一边不断附和着“是““对“

耶鲁公开课 - 1945年后的美国小说课程节选

One pigeon was jumping up and down a lot, another one was bobbing its head, and another one was doing kind of a little dance.

它们有的上蹿下跳,有的摇头晃脑,还有的独鸽乱舞

耶鲁公开课 - 金融市场课程节选

This doesn't mean the object is bobbing up and down.

它不表示物体在上下摆动

耶鲁公开课 - 基础物理课程节选