【www.shanpow.com--英语作文】
【一】:it的用法归纳
• Never be afraid of grammar
• Collect some examples;
• Watch them very carefully;
• Find out something in common;
• Try to use the rules ---- practise.
it用法完全归纳
一、it 作人称代词的用法
1. 指事物
作为人称代词，it 可以除人以外的一切事物或动物。如： I dropped my watch and it broke. 我把手表掉在地上摔坏了。 It’s hard work, but I enjoy it. 工作很辛苦，可是我乐意干。 “Where is the dog?” “It’s in the bedroom. ” “狗在哪?”“在卧室里”。
2. 指人
it 指人主要用于指不性别不明的婴儿或用于确认某人的身份。如：
Is it a boy or a girl? 是男孩还是女孩?
There is a knock on the door. It must be the postman. 有人在敲门，一定是邮递员。
【说明】在答语中，常用来指本人，如说 It’s me。
3. 代替某些代词
代词 it 还可用于代替指示代词this, that 以及复合不定代词 something, anything, nothing等。如：
“What’s this?” “It’s a new machine. ” “这是什么?”“是一种新机器”。
Nothing is wrong, is it? 没出什么问题，是吗?
二、it 作非人称代词的用法
1. 基本用法
it 作非人称代词的用法，主要用于指时间、距离、价值、天气、气候及温度等自然现象。如：
It’s too late to go there now. 现在去那儿已经太迟了。
It rained all day yesterday. 昨天下了一天的雨。
It can get very hot here. 这里有时会很热。
2. 用于某些句型
It’s time for sth. 该做某事了。
It’s time to do sth. 该做某事的时候了。
It’s time for sb to do sth. 某人该干某事了。
It’s (about / high) time + that-从句. 某人该做某事了。(从句谓语用过去式，有时也用“should+动词原形”)
It’s first (second) time + that-从句. 某人第几次干某事。(从句谓语用现在完成时)
It’s + 时间段 + since-从句. 自从……有一段时间了。
It’s + 时间段 + before-从句. 过多长的时间才……
三、it用作形式主语
1. 基本用法
当不定式、动名词、从句等复杂成分用作句子主语时，为保持句子平衡，通常把真正的主语放在句末，而在句首使用形式主语it。如：
It’s very important to remember this. 记住这一点很重要。
It’s hard work climbing mountains. 爬山是费劲的事。
It’s unknown when he will come. 他什么时候来还不知道。
2. 用作形式主语的的重要句型
(1) It + be + adj. for (of) sb to do sth 某人做某事……
It is hard for him to make up his mind. 他很难下定决心。
It was foolish of her to say such a thing. 她说那样的话，真是太蠢了。
【说明】介词 of 与 for 的区别是：of 用于指某人的性格、属性、特征等，介词for表示对象，意为“对……来说” (from )。
(2) It takes sb + 时间段 + to do sth. 某人做某事花了……时间
It takes years to master a new language. 要花多年的时间才能掌握一门新的语言。
【说明】此句型可以有以下多变种变体：It took me an hour to write the letter. =The letter took me an hour (to write). =I took an hour to write the letter. 我写这封信花了一个小时。
(3) It is up to sb to do sth. 该由某人做某事
It’s up to you to to make the choice. 得由你来作选择。
(4) it look (seem, appear, happen, occur) that [as if]„ 似
乎……
It seemed as though he didn’t recognize me. 他似乎没认出我来。
It happened that I was out when he called. 他打电话时我碰巧不在家。
(5) If it were not for„ / If it hadn’t been for„ 若不是因
为……
If it were not for their help, we couldn’t have got over thewww.shanpow.com_practise,的用法。
difficulties. 要不是他们帮助，这些困难我们不克服不了的。
四、it用作形式宾语
1. 基本用法
当不定式、动名词、从句等复杂成分用作宾语且其后跟有宾语补足语时，通常会在宾语补足语前使用形式宾语，而将真正的宾语移至句末。其基本结构为“动词+it+宾语补足语+不定式(动名词或从句)”。如：
I find it difficult to do the job well. 我发现做好这件事不容
易。
I think it best that you should stay here. 我认为你最好住这
儿。
We think it no use complaining. 我们认为抱怨是没有用的。
2. 用作形式宾语的几个特殊结构
(1) 动词+ it + that-从句。如：
I like it that you came. 你来了，我很高兴。
I take it (that) he will come on time. 我认为他会准时来的。 You can put it that it was arranged before. 你可以说这是以前安排的。
Rumor has it that the defence minister will soon resign. 据传
闻，国防部长不久就要辞职。
【说明】能用于此结构的动词不多，常见的有 have, take, put, like 等。
(2) 动词 + it + when (if)-从句。如：
I dislike it when you whistle. 我不爱听你吹口哨。(from
)
【二】:重点词语用法
重点词语用法
1．sometimes, sometime和some time的不同含义
1)sometimes＝at times，意思是“有时”，可置于句首、句中或句末。如：
①I have letters from him sometimes. 我有时候收到他的来信。
②Sometimes I come by train, but usually I come by car.
我有时坐火车来，但通常坐汽车来。
③It's sometimes warm and sometimes cold. 天气时冷时暖。
2)sometime(adv)“在某一时候”；而some time是一个名词词组，表示“一段时间”的意思。如： ①The foreign friends will come to our school sometime next week.
外国朋友将于下周某时来我们学校。
②We have known each other for some time. 我们相识有一段时间了。
2．advice的用法
advice是不可数名词，意为“劝告、忠告、建议”，可用some, much, a little, a piece of, pieces of等修饰，不能说many/a few advice。
advice常与动词搭配，构成下列词组：ask sb for advice, ask for advice,
follow/take sb's advice, give sb some advice on sth/how to do sth。如：
①Let's ask for the teacher's advice.我们去征求老师的意见吧。
②They gave a piece of advice on our work.
他们对我们的工作提出了一条建议。
③If you take my advice and work hard, you will pass the exam.
如果你听从我的劝告而努力学习，你就会通过考试。
④Can you give us some advice on how to improve our English?
你能给我们提一些关于怎样提高英语水平的建议吗？
【注意】on sb's advice 表示“按照某人的建议”。如：
①Did you act on the professor's advice? 你是按教授的建议去做的吗？
②On the doctor's advice, he gave up smoking. 听了医生的建议，他戒烟了。www.shanpow.com_practise,的用法。
3．follow的用法
1)＝come, arrive, go or leave after跟随；或=come next in time表示(时间或次序)接着，随着 ①She followed him into the room. 她跟着他进入房间。
②The teacher was followed by a group of students.
老师后面跟着一群学生。
③Monday follows Sunday. 星期天之后是星期一。
2)＝understand领悟，明白
①You are speaking too fast and we can't quite follow you.
你讲得太快，我们不太懂你的意思。
3)＝accept or take采纳
①I decide to follow his advice.我决定听从他的建议。
4)= go along沿……而行
①Follow(= go down) the path and you will see the farm-house.
顺着这条小路走，你就会看到那座农舍。
5)形容词following与the连用表示“接着的，其次的，下列的”。
①in the following year次年(＝ next)
4．some[s)m] adj. 的用法
1)some用于肯定句中，意为“一些，若干；有些”。例如：
①I have some questions to ask. 我有一些问题要问。
②Not all wood is hard, some wood is soft.
木料不一定都硬，也有软的。
2)some用于疑问句中，表示盼望得到肯定的答复或表示建议、请求等。例如：
①Aren't there some envelopes in that drawer?
那个抽屉里不是还有几只信封吗？
②Would you have some tea? 您喝茶吗？
3)some可表示“某一”之意。例如：
①He is working at some place in the north.
他在北方某地工作。
②Some person at the door is asking to see you. 门口有人要见你。
【注意】some还可用作代词，既可代替可数名词，也可代替不可数名词。
例如：
①Some of it is good. 其中一部分是好的。
②Some answered yes and some(或 others) answered no. 有的回答“是”，有的回答“不是”。
5．either的用法
either['aiJ+, 'i:J+] 可用作adj., pron., adv., conj.
1)either作代词时，意为“两者之一”，可单独使用，也可和of连用。of后面接复数名词，名词前面要用一个物主代词，指示代词或定冠词等。例如：
①Did you serve either of my last two campaigns?
我的上两次战役，你参加过其中的一次吗？
2)“either of+ 名词词组”结构在句中作主语时，动词一般用单数。例如：
①Either of the girls is capable of doing the job.
这两个女孩子都有能力做这项工作。
3)either也可用作形容词，一般指“这个或那个”，表示两者之中任一个。
例如：
①You may use either hoe.两把锄头中你可以随便用哪一把。
4)either也可用作副词，用于否定句或否定词组后加强语气，意为“也，而且，根本”。例如： ①If he doesn't go, I won't, either. 如果他不去，我也不去。
5)either 也可用作连词。意思是“或者，要么(一般只用于either…or的结构中)”。例如： ①Either you come in person, or you entrust someone with the matter.
你要么自己来，要么托人办理此事。
6．want[w&nt] vt. 的用法
1)表示“想，要，希望”之意：
(1)跟不定式：
①She wants to go Italy. 他想到意大利去。 【注意】want一般不宜用进行时，但有时用进行时强调，“一直想”。
例如：
②The children are always wanting to see you. 孩子们老想见你。
(2)跟带不定式的复合结构：
①She wants me to go with her. 她让我跟她一起去。
(3)跟带分词的复合结构：
①Do you want this box opened?你要把这匣子打开吗？
②We don't want you getting into trouble. 我们不希望你碰到麻烦。
(4)跟名词或代词：
①You are wanted on the phone. 有你的电话。
②What do you want? 你要什么？
2)表示“需要(接近need)”之意：
(1)跟名词或代词：
①Do you want anything more? 你还要别的吗？
②These flowers want water. 这些花需要水。
(2)跟动词-ing形式：
①The room wants cleaning(=to be cleaned).房间需要打扫。
(3)表示“短缺；差”之意。如：
①It wants half an hour to the appointed time.
到约定的时间还有半小时。
②The book wants a page at the end. 书的结尾缺一页。
7．improve[im' pru:v] vt. 改善，改进，提高。例如：
①The factory is continuously improving the quality of their products.
这个工厂正在不断提高他们的产品质量。
②The soil has been much improved.土壤已被改良。
③The machine was improved by a young worker.
这台机器是由一位青年工人改良的。
④This is not good enough; I want to improve it.
这还不够好，我要加以改进。
⑤He gave us some advice on how to improve my English.
他就如何提高我的英语水平给了我一些忠告。
⑥Their life has been much improved.
他们的生活有了很大改善。
【注意】 improvement n. 改进，改良(不可数名词)。例如：
①There was some improvement in his health.
他健康方面有些好转。
8．about的用法
about[+'baut] prep. 关于，对于。注意在不同的场合下有不同的译法。其主要用法如下：
1)和某些动词连用：
①I want to consult you. It's about Xiao Li.
我想跟你商量一下，是关于小李的事。
②Did she say anything about what to do?
她说怎么办了吗？
③What have you been thinking about? 你在想什么？
④He doesn' t worry much about me. 他并不太为我着急。
⑤He used to care only about his own family.
过去他只关心自己一家。
2)和某些形容词连用：
①He said he was sorry about it. 他说这事他很抱歉。
②He doesn't seem to be very happy about it.
对这他似乎不太高兴。
③We were anxious about him.我们都很为他着急。
④I was a bit uneasy about leaving them like that.
就这样离开了他们，我感到有点不安。
3)和某些名词或代词连用：
①It was a story about slum life in Chicago.
这是一篇关于芝加哥贫民窟生活情况的故事。
②I have sent you all the information I have about it.
我把所了解的这方面的情况都告诉你了。
③I have expressed my ideas about this before.
过去我发表过关于这问题的看法。
④I learned something about how radios are made.
我对无线电是怎样制造的有了一些了解。
4)和一些词组连用：
①We mustn't be in a hurry about such things.
这种事情我们不能匆忙行事。
②They are divided in their opinions about it.
对此他们意见有分歧。
③He did not know what to do about it. 他不知如何是好。
④She asked me a few questions about how I felt.
他就我的感受问了几个问题。
9．prepare[pri'p#+]v.准备；调制，配制。例如：
①The teacher has already prepared his lessons.
老师已经备了课。
②Our headmaster is preparing a report for radio broadcast.
我们校长正在给电台广播准备一篇讲稿。
③The secretary is busy preparing the rnaterials for the party.
秘书正忙着给晚会准备材料。
【注意】
1)短语prepare for 表示“为……做准备”。例如：
①It took us a week to prepare for the mid-term examination.
我们花了一周的时间准备期中考试。
2)be prepared to do something 意为“有能力而且愿意做某事”。例如： ①That company is prepared to supply the seed the peasants asked for.
农民们要的种子，那家公司有能力而且愿意供应。
10．practise 的用法
1)practise用作及物动词时后面可接名词、动名词，不能接不定式。practise的基本意思是“练习”、“训练”，也可用来表示“实行”和“开业从事于”。如：
①She has been practising the some tune on the piano for nearly an hour.
她在钢琴上一直练同一个调子已近一个小时了。
②They're practising singing the new song.
他们正在练习唱那首新歌。
③We practised pronouncing the sound again and again.
我们一遍又一遍地练习发这个音。
④It's very important to practise listening.
练习听力是非常重要的。
⑤He practised tennis/the piano for two hours every day.
他每天下午练两个小时网球/钢琴。
⑥Our income is getting smaller and we have to practise economy.www.shanpow.com_practise,的用法。
我们的收入变少了，所以只好厉行节约。
⑦He began to practise medicine/the law in his early twenties.
他在二十刚出头时就开业行医/开始做律师了。
2)practise可用作不及物动词
① Practise more and you'll make progress.
勤练习，你一定会进步的。
②Don' t forget to practise after class. 课后别忘了练习。
【注意】 practise的名词是 practice，两词发音一样，practice为不可数名词。Practice makes perfect. 是一句谚语，意思是“熟能生巧”。 put the idea into practice表示“把思想付诸实践”。
11．explanation 的用法
explanation n. 解释。可有复数形式explanations; give explanation of/for sth.对……加以解释。
【注意】在下列句中几个词义的区别：
①What's your explanation for being late?
你能解释一下你迟到的原因吗？ ②What' s your reason for being late?你为什么迟到？ ③What' s your excuse for being late again?
这次你又为迟到找出什么借口来了？(很不满意)
重要词组短语
1．pick up的六种用法
1)拾起，拿起。如：
①The boy picked up all his toys and put them into a box.
那男孩把所有的玩具都捡起来，放在一只盒子里。
②She picked up a magazine that was lying on the table.
她拿起摆在桌上的一本杂志。
2)(用车辆)去接(某人)，(在中途)搭载。如：
①He stopped the car to pick up an old man.他停下来让一位老人搭车。
②We'll send someone to pick him up. 我们将派人用车把他接走。
3)(从收音机里)收到，接收。如：
①My radio can pick up“Follow Me”very clearly.
我的收音机收听“跟我学”很清楚。
②Can you pick up London on the radio?
你的收音机能收听到伦敦的电台吗？
4)(跌倒后)站起来。如：
①I slipped and fell, but I quickly picked myself up.
我滑倒了，但很快就爬了起来。
5)偶然找到，偶然学会或获得。如：
①In his fifties, he picked up another language.
他在五十几岁时，自学了另一门语言。
6)恢复(健康)。如：
①This patient is beginning to pick up now.现在这位病人开始恢复健康了。
②You'll soon pick up your health when you go to the countryside.
你到了乡下很快会恢复健康的。
【三】:practise 的用法详解
practise的时态用法：过去式：practised; 过去分词：practised ;现在分词：practising.下面学习啦小编和大家讲解一下practise的语态用法。
practise对的用法1：用作及物动词时后面可接名词、动名词，不能接不定式。practise的基本意思是“练习”、“训练”，也可用来表示“实行”和“开业从事于”。如：
①She has been practising the some tune on the piano for nearly an hour.
她在钢琴上一直练同一个调子已近一个小时了。
②They”re practising singing the new song.
他们正在练习唱那首新歌。
③We practised pronouncing the sound again and again.
我们一遍又一遍地练习发这个音。
④It”s very important to practise listening.
练习听力是非常重要的。
⑤He practised tennis/the piano for two hours every day.
他每天下午练两个小时网球/钢琴。
⑥Our income is getting smaller and we have to practise economy.
我们的收入变少了，所以只好厉行节约。
⑦He began to practise medicine/the law in his early twenties.
他在二十刚出头时就开业行医/开始做律师了。
practise对的用法2：可用作不及物动词
① Practise more and you”ll make progress.
勤练习，你一定会进步的。
②Don” t forget to practise after class. 课后别忘了练习。
【注意】 practise的名词是 practice，两词发音一样，practice为不可数名词。Practice makes perfect. 是一句谚语，意思是“熟能生巧”。 put the idea into practice表示“把思想付诸实践”。
Before she went abroad, she spent as much time as she could________English.
to practise to speak
practising speaking
to practise speaking
practising to speak
答：
B，在她出国之前，她用了很多时间练习英语。
这里考查两个动词的搭配。
第一个，spend time on sth/ in doing sth , in可省略，花时间做某事
第二个，practise 后接动名词，不接不定式。
practise 的用法详解相关文章：
1.practise 的用法详解
2.offer的用法
3.非谓语动词的语法知识点详解
4.动词suggest和Express的用法区别
【四】:英语短语not only … but also的用法
短语not only … but also在英语学习中经常见到，那你清楚它的用法吗?让学习啦小编来为你介绍，希望能对你有所帮助：
1、 not only 位于句首时, 该句的主语和谓语要部分倒装。
Not only does the sun give us light but also it gives us heat.
太阳不仅给了我们阳光, 也给了我们热量。
Not only did he speak English correctly, but also he speaks it fluently.
他不仅英语说的正确, 还说得流利。
Not only is this young man clever but also he is hardworking.
这个小伙子不仅聪明, 也很勤奋。
2、not only … but also 不能用在否定句中。例如：
他们既不怕苦, 也不怕死。
误 They don't fear not only hardship but also death.
正 They fear neither hardship nor death.
正 They don't fear either hardship or death.
3、not only … but also 连接两个名词作主语时, 谓语动词要根据but also 后的名词决定单、复数(就近原则)。例如：
Not only the students but also the teacher was against the plan.
不仅学生们, 还有那位老师都反对该项计划。(the teacher was...)
Not only the teacher but also the students were against the plan.
不仅那位老师, 还有学生们…… (the students were)
4、not only … but also 和两个部分, 通常必须是对称的并列成分。例如, 连接两个主语、连接两个状语等等。
Not only Mr Lin but also his son joined the Party two years ago.
不仅林先生而且他的儿子在两年前都入了党。(连接两个主语)
I not only play tennis but also practise shooting.
我不仅打网球, 还练习射击。 (连接两个谓语动词)
He plays not only the piano but also the violin.
他不仅弹钢琴, 也拉提琴。 (连接两个宾语)
They speak English not only in class but also in the dormitory.
他们不仅在课堂上说英语, 在宿舍里也说。(连接两个地点状语)
注意 ：下列句子是不规范的用法：
He not only plays the piano but also the violin.
因为not only plays the piano 与 but also the violin 在语法结构上不对称。
5. not only 不能拆开使用, 但 but also 却可以分开使用。例如：
The area was not only hit by an unexpected heavy rain, but some bridges were also washed away.
这个地区不仅受到了暴雨袭击，而且部分桥梁也被冲走了。
6、在not only...but also 搭配中，可以只用but 或只用also, 甚至可以把 but also 都省略掉。例如：
I not only heard it but ( also ) saw it.
我不仅听到了，而且看到了。
He was not only compelled to stay at home, ( but ) also forbidden to see his friend.
他不仅被近留在家里，还被禁止去看他的朋友。
She not only finished the task ahead of time, ( but also ) she came to help us.
她不仅提前完成了工作，还帮助我们。
7、还可以用 besides, furthermore, moreover, in addition 等替代 but also. 例如：
Not only was there no food, but also (或 furthermore, besides, moreover, in addition ) there was no water.
不仅没有食物，也没有水。
8、可以用 merely, just, simply 等替代 not only 中的 only. 例如：
They not merely ( 或 just, simply ) broke into his office and stole his books but also tore up his manus cripts.
他们不仅闯进了他的办公室，偷走了他的书，而且撕碎了他的手稿。
9、not only ... but also ... 相当于... as well as ... 结构。两者强调的都是后面那一部分的内容，翻译时 要先译 as well as 后面的词。例如：
The child is not only healthy but also lively.
( = The child is lively as well as healthy. )
这孩子既健康又活泼。
It concerns not only me but also you.
( = It concerns you as well as me. )
这件事不但与我有关, 而且也与你有关。
10、可以用 but … too / as well 替代but also. 例如：
She not only sang well but danced gracefully too ( or as well ) .
她不仅歌唱得好，舞也跳得好。
not only … but also双语例句
1、Children's television not only entertains but also teaches.
儿童电视节目不仅有娱乐性而且还有教育意义。
2、In particular, local pressures if reproduced in other countries such as India may be the best path for dealing with not only pollution but also global warming.
尤其需要提及的是，如果中国这种来自国内的压力重现于印度等国，它就有可能成为不仅是应对环境污染，甚至是应对全球变暖的最佳路径。
3、The room is not only large but also beautiful.
这房间不但大而且漂亮。
【五】:初二英语必备知识点：定冠词的常见用法
掌握每一个语法知识，会让你在学习英语的时候更加如鱼得水。下面是学习啦小编收集整理的初二英语《定冠词的常见用法》的必备知识点以供大家学习。
初二英语必备知识点：定冠词的常见用法
定冠词也出现在其他11种情况中，非同时注意不可。
⑴用在单数名词前面，以代表同类的人或物，如：
The ox is a useful animal for farmers.
This type of work is easier for the teacher than for the student.
但当涉及 man 和 woman 这两个名词时，一般上不必用 the ：
Man is mortal.
Woman differs from man in many ways.
⑵用在单数名词前面来表示有关名词的抽象概念，如：
Don't play the fool.
Peter is fond of the bottle.
⑶用在数目字前面，如：
Mr Li is somewhere in the 30s.
She was not yet born in the 50s.
⑷用在测量单位前面，以表示“每”(each/per)，如：
Some factory workers are paid by the hour.
This car usually does 15 kilometres to the litre.
⑸用在比较级形容词或副词之前，以加强其意义，如：
The teacher explained the idea again, but his students were none the wiser.
Your mind will function all the better if you have some time away from your work.
⑹用在“the more/better……the more/better……”结构里，如：
The more we practise, the more we improve.
The better the staff, the better the performance.
⑺用在乐器名称之前，如：
The piano sounds better than the organ.
⑻用在剧院、电影院之前，如：
Do you often go to the cinema?
Tom went to the Lido last week.
⑼用在四个方向之前，如：
The sun rises in the east and sets in the west.
⑽用在复数姓氏之前，以表示有关家人，如：
The Browns will visit us tonight.
⑾用在某些惯用语之前，如：
We know the ins and outs of the matter.
Compare the pros and cons before you make your decision.
初二英语必备知识点：疑问附加语isn't it
"John is smart, isn't it?"
这个疑问句里的附加语(question tag)对吗?如果是不对的话，错在哪里?
在公共场所或办公室里，只要稍为留心，不难听到“ isn't it ? ”这个附加语。这种疑问句是英文几种疑问句中的一种，主要的用途在强制答话人提供问话人心目中的答案。
这个疑问句有一定的格式，即：
·肯定叙述句(affirmative statement)+否定附加语(见例 ①及②)
·否定叙述句(negative statement)+肯定附加语(见例③及 ④)
①Mary is happy, isn't she?
②They will come, won't they?
③Mary isn't sad, is she?
④They won't come, will they?
此外，附加语中的代名词(pronoun)和助动词(auxiliary verb)必须和叙述句中的相符。
这类疑问句看似简单，其实容易出差错。其中一个错误便是附加语的时态(tense)不对，如：
⑤You could hardly expect him to help you, can you?
⑥The minister will talk about regional cooperation, wouldn't he ?
另外一种错误是助动词的错用，如：
⑦The clerks are working hard, don't they?
⑧Betty won't be a sportswoman, can she?
“isn't it”的滥用
最常见的错误来自“isn't it”的滥用，如：
⑨Jason likes this book very much , isn't it?
⑩She can sing well, isn't it?
11.Our team won, isn't it?
12.Young Singaporeans have become achievement - oriented , isn't it?
13.All our teachers are dedicated, isn't it?
14.They will go shopping on Sunday, isn't it?
这6个错误的附加语改正如下：
⑨Jason likes this book very much, doesn't he?
⑩She can sing well, can't she?
11.Our team won, didn't it?
12.Young Singaporeans have become achievement - oriented, haven't they?
13.All our teachers are dedicated, aren't they?
14.They will go shopping on Sunday, won't they?
"lsn't it ? "在下列3个句子中才是正确的用法：
15.It is fine today, isn't it?
16.That story book is interesting, isn't it?
17.It is worthwhile learning a second language well, isn't it?
现在再看看“John is smart , isn't it ?”错在哪里。很明显的，错在附加语里的代名词：应该是“he ”，不是“it”，全句如下：John is smart, isn't he?
