nod既可以作动词，也可以作名词。该词作动词和名词使相关用法如下：
1. nod作动词
（1）to move your head up and down especially in order to show agreement or understanding尤指表示赞同或理解而点头
例如：Mom nodded her head sympathetically.
妈妈同情地点了点头。
Corbett nodded his acceptance.
科比特点头表示认可。
（2）to move your head down and up again once in order to greet someone or give someone a sign to do somethin***头致意，点头示意
例如：The judge nodded at the foreman to proceed.
法官点头示意首席陪审官继续说。
2. nod作名词，表示an act of nodding（点头）。
例如：The woman greeted US with a nod of the head.
那个女人向我们点点头打招呼。
I showed the doorman my card and he gave a friendly nod.
我校门卫出示了卡片，他友善地点了点头。
