Watch动词：看，注视，观看，观察（含有注意看，或仔细观察之含义）
Watch what I do, then you try.
你注意看我的动作，然后试着做。
Parents can't be expected to watch their children 24 hours a day.
父母不可能每天24小时照看孩子。
Thousands of people paid good money to watch the band perform.
成千上万的人花很多钱去观看这支乐队的演出。
We watched to see what would happen next.
我们注视着下一步要发生的事情。
She felt he was watching her every move.
她觉得他在注意她的一举一动。
一、watch是感觉动词，其后接动词充当宾语补足语的动词不定式不带to,这个用法（主动语态句子用法）和其他的感觉动词see,hear,observe,等词用法一样；但是这个词比较特殊例外，没有所谓的变被动结构时其后的不定式必须带to之用法：
We watched the children skip rope.
我们看孩子们跳绳。
Watch作“看，观察”不可用于被动结构；但是作为“监视”是可以用于被固定结构的。当然也可以这样用：
She watched the kids playing in the yard.
她看着孩子们在院子里玩。
They watched the bus disappear into the distance.
他们注视着公共汽车消失在远方。
二、watch是个持（延）续性动词，请看：
They watched the train until it disappeared in the distance.
他们一直注视着火车消失在远方。（注意这里的watched,不可以换成saw, observed等短暂性动词，即所谓的瞬间动词）
Mother told Jim to watch the milk until it boiled and then turn off the gas. (上海高考真题)
妈妈告诉吉姆看着牛奶直到牛奶沸腾后把煤气关掉。
（注意这里的watched,不可以换成saw, observed等短暂性动词，即所谓的瞬间动词）
until意为“到…时，直到…为止”，既可以用作介词，又可以用作连词。
There will be a wonderful match tonight. I will watch it until it finishes.
今晚有一场精彩的比赛。我要看完它。（until用作连词）
That may last until Friday. 那也许会持续到周五。 （until用作介词）
顺便讨论until的用法：
1）用于肯定句，意为“到…时；直到…为止”，引导时间状语从句，主句谓语动词用持（延）续性动词。
I shall live here until/till she arrives.我将等到她回来为止。
I will wait here until 5 o'clock.
我会在这等到五点。
The store is open until midnight.
这家商店开放至午夜。
She worked diligently until the project was completed.
她一直努力工作，直到项目完成。
I will stay here until you come back. 我将呆在这里直到你回来。Continue in this direction until you see a sign.一直沿着这个方向走，直到你看见一个指示牌为止。
He worked until it was dark. 他一直工作到天黑。
He will keep studying until he passes the exam.
他会一直学习，直到通过考试。
注意：live ，wait, open, work ,stay，continue，work，keep是持（延）续性动词
Tom was a member of the English club until last year.
汤姆直到去年一直是英语俱乐部的会员。（was a member of 不可用join代替）
2）用于否定句，not...until的意思是“直到…才”，引导时间状语从句，主句谓语动词一般用短暂性动词。短暂性动词就是瞬间完成的动词，如go, come, leave, die, arrive, buy, enter等, 以enter为例，我们“进”这个动作一瞬间就完成了，不会持续。
She will not leave until you apologize.
在你道歉之前，她不会离开。
We cannot start the meeting until everyone is present.
在每个人到场之前，我们无法开始会议。
I hadn’t realized she was foreign until she spoke. 直到她讲话我才意识到她是外国人。
I didn’t manage to do it until you had explained now. 直到你解释了以后我才会做。
（manage是短暂性动词，manage to do something努力做某事，设法做某事，设法做成某事）
He didn’t leave the office until he finished his work.他完成工作才离开了办公室。
I will not speak until my lawyer comes.
律师来了，我才开口说话。
注意：leave ，start ，realize，manage，leave，speak是短暂性动词。
3). 时态问题
①until引导的时间状语从句用一般现在时表将来的动作或状态,即“主将从现”。
如：I won’t leave until he comes back.我直到他回来才离开。
She will stay here until the rain stops.她将呆在这里直到雨停。
②主句过去时，从句过去时。
如：I slept until he called me.我睡了直到他电话我。
③主句一般时，从句一般时。
如：I often do homework until my mum asks me to stop it.我常做作业到我妈妈叫我停下来为止。
4）Not...until的强调句式：
It is/was not until... that...(注意that从句中谓语不能再用否定。)
Her husband didn’t arrive home until late in the evening.(原句)
It was not until late in the evening that her husband arrived home.
直到很晚的时候她的丈夫才回到家。
We didn’t get off the bus until it stopped. (原句)
It was not until it stopped that we got off the bus. 直到公共汽车停下我们才下车。
5）Not...until的倒装句句式：
Not until ...+助动词/系动词/情态动词+主语+其他。
即：not until+词组放在句首时，后面谓语部分要使用部分倒装，即只把谓语部分的助动词/系动词/情态动词提前，而谓语部分的实义动词依然放在主语的后面；not until+从句放在句首时，后面的主句谓语部分要使用部分倒装,并且主句不能再用否定。（注意：从句不倒装）
将上面的两个例句改成倒装句
Not until late in the morning did her husband arrive home.直到很晚的时候她的丈夫才回到家。
(注意：这里arrived要变成原形，前面要使用助动词did。)
Not until it stopped did we get off the bus.
直到公共汽车停下我们才下车。
(这里主句使用助动词did，got off 变成原形get off.)
下面再看这个句子
He didn’t understand me until I told it to him.
直到我告诉他才明白我的意思。
这里didn’t understand是主句的复合谓语，把它改成倒装句时，只把did提前，understand不能提前，主句改为肯定句。为
Not until I told it to him did he understand me.
改为强调句It was not until I told it to him that he understood me.直到我告诉他才明白我的意思。
我们再来看个句子:Until that happens, you need to protect yourself.
在那之前，你必须保护你自己。(这里until+从句提前，主句不倒装。只有not until放在句首，后面才倒装。)
我们再来翻译一个句子:直到地震两周后他才发现他的妈妈活着。
Not until two weeks after the earthquake did he find his mother alive.
(he后面的发现不能用found,必须用原形find。)
直到她妈妈给她读了一个故事这个小女孩才睡着。
Not until her mother read her a story did the little girl fall asleep.
或者 The little girl didn’t fall asleep until her mother read her a story.
例句You can’t have this football back until you promise not to kick it in class.
直到你保证不再上课时踢球你才能拿回这个球。
改为倒装句Not until you promise not to kick it in class can you have this football back.
直到你保证不再上课时踢球你才能拿回这个球。
改为强调句It is not until you promise not to kick it in class that you can have this football back.直到你保证不再上课时踢球你才能拿回这个球。
三、有关watch的短语：
Watch TV=look at TV看电视
Watch TV/ a film=see TV/ a film看电视（电影）
watch the clock盯着钟表（算计着不超过规定的工作时间，或只盼望下班而无心工作）
I started to watch the clock about halfway through the class.
I started to watch the clock about halfway through the class.
课大约上了一半，我就开始不停地看时间。
watch the time注意时间（以便按时完成或到达）
I'll have to watch the time. I need to leave early today.
我得看着点时间。今天我要早走。
watch your mouth/tongue
说话当心；嘴上留个把门的
watch the world go by
闲看人来人往；静观众生百态
We sat outside a cafe, watching the world go by.
我们坐在一家小餐馆外面，望着眼前来来往往的人们。
Many old people sit in their rooms by themselves and watch the world go by.
许多老人独自待在家里，静观众生百态。
mind/watch your language
谨慎措辞；留神言辞
Watch your language, young man!
年轻人，注意你的言谈！
mind/watch your step走路小心；言行小心谨慎
on watch值班
on the watch （for）密切注视着、警惕着；对……留神
Apart from two men on watch in the engine-room, everyone was asleep.
除了两个人在机房值班外，其他人都在睡觉。
Environmentalists will be on the watch for damage to wildlife.
环境保护主义者将会密切关注对野生动物造成的伤害。
Be on the watch for thieves.
要提防小偷。
watch out小心；留神；注意
Watch out! There's a car coming!
小心！汽车来了！
watch out for sb/sth密切注意；留意；小心；当心
The cashiers were asked to watch out for forged banknotes.
出纳员接到要求，要注意伪钞。
Watch out for the stairs─they're steep.
小心楼梯，这些台阶很陡。
watch over sb/sth照管；监督；保护
keep watch警戒;守卫
Jose, as usual, had climbed a tree to keep watch.
乔斯像往常一样爬到树上放哨。
keep a close eye/watch on sb/sth
密切注视；严密监视
Over the next few months we will keep a close eye on sales.
在今后的几个月里我们将密切关注销售情况。
US officials have been keeping close watch on the situation.
美国官员一直密切注意着事态的发展。
The government is keeping a close watch on how the situation develops.
政府正在密切注视着形势的发展。