1.nod的基本意思是“点头”,多用于表示同意或打招呼等,引申可表示“打盹”“打瞌睡”“(树梢、花等)上下(或左右)摇摆”“疏忽”“出错”等。
2.nod既可用作及物动词,也可用作不及物动词。用作及物动词时,可接名词或代词作宾语或接双宾语,其间接宾语可以转化为介词to的宾语。作不及物动词时,其后常接介词to或at,也可接动词不定式作目的状语。
3.nod是瞬间动词,如表示动作重复,须用进行体。

nod at〔to〕(v.+prep.)
向…点头bow the head slightly and quickly (as a sign of agreement or as a familiar greeting) to
▲nod at〔to〕 sb/sth
He nodded at us.他对我们点头。
I nodded at him in greeting. 我向他点头打招呼。
He nodded at me as he passed.他走过去的时候向我点头打招呼。
She took a pull at the bottle then nodded to me.她从瓶中喝了一口,然后向我点点头。
He nodded to me in a friendly way.他友好地向我点点头。
She nodded to me with a smile.她微笑着向我点点头。
She nodded to us from across the room.她从房间的另一头向我们点头打招呼。
He nodded to me in greeting when I went into the room.当我进入房间时,他向我点头打招呼。
“Ask him,”said Mary, nodding to John.“问他,”玛丽边说边朝约翰点了一下头。
He nodded to me to leave the room.他点头示意我离开房间。

nod back(v.+adv.)
以点头(方式)示意(某人)回去bow the head slightly as a sign of agreement back
▲nod sb ⇔ back
The teacher nodded me back.老师点头示意让我回来。

nod into(v.+prep.)
以点头(方式)示意(某人)进入bow the head slightly as a sign of agreement into
▲nod sb into sth
The boss nodded me into his office.老板点点头示意我进他办公室。

nod off(v.+adv.)
〈非正〉打盹fall asleep accidentally
▲nod off
I hope the teacher didn't notice that I nodded off in the class.但愿老师没发现我在课堂上打瞌睡。
He nodded off during the meeting and didn't hear what was said.开会时,他打瞌睡,会上说什么他一点也没听。
I often nod off for a little after lunch.我常在午饭后打个盹。
He nodded off while she was speaking to him.她对他说话时,他睡着了。

用作不及物动词
▲S+～(+A)
I asked her if she could come and she nodded.我问她是否能来,她点头表示同意。
The president nodded and every one sat down around the table.主席点了点头,每个人都围着桌子坐下来。
He was nodding.他连连点头。
She stared at the flowers nodding in the wind.她凝视着随风摆动的花朵。
The teacher caught her nodding.老师发现她在打瞌睡。
Homer sometimes nods.智者千虑,必有一失〔老虎也有打盹时〕。
▲S+～+to-v
He nodded to show that he understood.他点头表示他懂了。
用作及物动词
▲S+～+n./pron.
She nodded her head when she passed me in the street.当她在街上走过我身旁时,她向我点了点头。
Father quietly nodded his consent.父亲温和地点头同意。
The teacher nodded approval.老师点头表示赞成。
They nodded their farewell.他们点头告别。
They all nodded a final good-night.他们最后都点头互祝晚安。
用作双宾动词
▲S+～+pron./n.+n./pron.
I nod her a welcome.我向她点头表示欢迎。
▲S+～+n./pron.+to pron./n.
He nodded a welcome to Mary. 他向玛丽点头表示欢迎。

她向他点头表示欢迎。
［误］  She nodded a welcome for him.
［正］  She nodded him a welcome.
［正］  She nodded a welcome to him.
［析］  nod用作及物动词时可接双宾语,其间接宾语可以转化为介词to的宾语,但不可转化为for的宾语。

nod用作名词时意思是“点头”,多用单数形式,常与介词with连用,表示伴随状态。

a nod's as good as a wink
不用多说 used to show that the speaker understands a situation without needing a full explanation
A nod's as good as a wink, she was sacked for incompetence.不用多说,她因不称职而被解雇。

on the nod
无人反对地 by general agreement and without being talked about
The chairman's proposals are usually passed on the nod at the shareholders's meeting.在股东会上主席的提议通常在无人反对的情况下通过。

The judges gave the nod to the winning challenger.裁判们对挑战者的胜利给予确认。
She gave me a nod as she passed.她走过时对我点头招呼。
From time to time, she gave him an encouraging nod.她不时对他点头鼓励。
Mark approves with a nod.马克点头表示同意。

他点头作答。
［误］  He answered with nods.
［正］  He answered with a nod.
［析］  nod用作名词时一般用单数,多与with a连用,表示伴随状态。

［同义词］ v.  agree, assent, slump n.  gesture, greeting, indication, sign
［词源］  ＜古英语nodden(点头)