It引起的几个易混淆的时间句型

It 引起的几个易混淆的时间句型 在学习中 同学生们对 It be 时间 从句 这个结构经常混淆不清 下面逐一进行分析 1 It be 时间 since clause 这个句型表示从 since 从句谓语动作发生以后到现在或过去所经过的一段时间 意为 自从 以来已多久了 主句多用一般现在时 从句用一般过去时 如果表示过去的情况 主 句用一般过去时 从句用过去完成时 或主句用过去完成时 从句用一般过去时 例如 It is three years since his father passed away 从现在算起 It was 10 years since they married 从过去算起 It had been fifteen years since she left Shanghai 从过去算起 30 years has passed since we joined the Party 从现在算起 2 It be 时间 before clause 这个句型中的时间一般为表示一段时间的词语 如 long years months weeks days hours minutes 主句中的谓语动词用肯定式 意为 过多长时间才 主句的谓语动词是否 定式时 意为 没过多长时间就 主句的时态可用过去时 was 或将来时 will be 用 was 时 before 从句的动词用一般过去时 用 will be 时 before 从句常用一般现在时 例如 It was not long before she learned those poems by heart 她没过多久就背会了那些诗歌 It was long before the police arrived 过了很久警察才来 It will be hours before he makes a decision 要过好几个小时他才会作出决定 It will not be hours before meet again 要不了几个小时我们还会再见面的 3 It be 时间 when clause 这个句型中 it 指时间 而且表示时间的词语前没有介词 时间一般为具体时间 主句中的 谓语动词和从句中的谓语动词在时态上一般是一致的 主句是 will be when 从句用一般现 在时代替将来时 例如 It was already 8 o clock when we got home It was the next morning when we finished our work It will be midnight when they get there 4 It be 时间 that clause 这个句型是个强调句型 例如 It was two years ago that he made an important invention 原句是 He made an important invention two years ago It was at 5 o clock that he practised playing the violin in the morning 原句是 He practised playing the violin at 5 o clock in the morning 比较 It was 5 o clock when he started in the morning 5 o clock 前没有介词 这是个定语从句 5 It be time that clause 这个句型属虚拟语气结构 不管主句中用的是 is 或 was that 从句都须用动词的过去式 或 should 动词原型 但不及用过去式普通 在 time 之前有时可加上 high 或 about 以加强 语气 例如 It is time that we handed in our exercises It is time that we should hand in our exercises It is high time that she wrote a letter to her boyfriend 6 It This That the first second third time that clause 这个句型表示截止到说话时为止的某人的一种经历 关键是注意 time 前有序数词 主句是 is 时 从句要用现在完成时 如果主句用一般过去时 was 则从句须相应地用过去完成 时 例如 This is the first time that these Europeans have visited the Great Wall It was the fifth time that I had paid a friendly visit to Africa 二 It 代替从句作形式主语的常见句型 1 it 代替连词 that 引导的从句作形式主语 1 it be 过去分词 that 从句 It s said that Tom has come back from abroad 据说汤姆已经从国外回来了 It was reported that dozens of children died in the accident 据报导 数十名儿童在事故中死亡 可用于该句型的过去分词还有 known thought told believed hoped announced expected decided suggested 等 该句型常可以转换成含有宾语从句的复合句或者含有不定式作主补 的简单句 如 It s said that Tom has come back from abroad People say that Tom has come back from abroad He is said to have come back from abroad 2 It be 名词词组 that 从句 It s a pity that he can t swim for his age 真遗憾 就他的年龄来讲 他竟不会游泳 It s a wonder that you could finish such a hard task in such a short time 真奇怪 你竟能在如此 短的时间内完成艰巨的任务 可用于该句型的名词词组还有 an honour a good thing a fact a surprise good news 等 3 It be seem 形容词 that 从句 It is likely that they will beat us tonight 今晚很可能他们会赢我们 It doesn t seem that she will give us a hand 她帮我们的可能性似乎不太大 可用于此句型的开容词还有 wonderful true good right wrong un important useless surprising clear possible unusual lucky certain 等 4 It seem appear happen that 从句 It seems that he enjoys pop songs very much 看来他非常喜欢流行歌曲 It appears that Tom might change his mind 看来汤姆会改变主意 It happened that I went out that day 碰巧我那天外出了 注意 句型 4 可转换成含不定式的简单句 如上述句子可转换为 He seems to enjoy pop music very much Tom appears to change his mind I happened to go out that day 2 it 代替连接代词或连接副词引导的从句作形式主语 1 It is known not decided not made clear found out discussed being discussed being considered a question uncertain 等 连接代词或连接副词引导的从句 It is still a question when we shall have our sports meet 我们将什么时候举行运动会还是一个 问题 It is uncertain whether he can attend this conference or not 他能否来开会还不能确定 2 It doesn t matter doesn t matter too much doesn t make too much difference 等 连接代词 或连接副词引导的从句 如 It doesn t matter whether we go together or separately 我们一起去还是分开去都可以 It doesn t matter too much to me what you do or where you go 你做什么或去什么地方 对我 都无关紧要 动脑动手 单元能力立体检测 一 It 与高考题 1 Tom s mother kept telling him that he should work harder but didn t help A he B which C she D it 答案与简析 选 D 测试 it 用作人称代词 代替前文提到过的事物 又如 1 The light in the office is still on Oh I forgot A turning it off B turn it off C to turn it off D having turned it off 2 Have you heard the news about Tom No what A is it B it is C are they D they are 3 If you don t know the word why don t you in the dictionary A look at it B look after it C look up it D look it up 答案 1 3 CAD 值得注意的是 由动词和副词组成的短语动词用 it 作宾语时 it 应 置于动词和副词之间 2 Is necessary to tell his father everything A it B that C what D he 答案与简析 选 A 测试 it 用作形式主语 代替由不定式 或不定式复合结构 动名 词或从句表示的真正主语 又如 1 Is possible to fly to the moon in a spaceship A now B man C that D it 2 Is necessary to complete the design before National Day A this B that C he D it 3 Does matter if he can t finish the job on time A this B that C he D it 4 It worried a bit her hair was turning grey A while B that C if D for 答案 1 4 DDDB 3 I don t think possible to master a foreign language without much memory work A this B that C its D it 答案与简析 选 D 测试 it 用作形式宾语 代替由不定式 动名词或从句表示的真正宾 语 当宾语有自己的补足语时 用 it 作形式宾语 真正宾语放在补足语之后 常用这种句 型的动词有 think make find feel consider 等 4 Was it in this palace the last emperor died A that B in which C in where D which 答案与简析 选 A 测试 it 用在强调结构中 为了强调句子的某一成分 通常是主语 宾语或状语 常用强调 It is was 被强调成分 that 或 who 被强调部分指人时用 that 或 who 在其它情况下 包括强调时间或地点状语 用 that 又如 1 Was it during the Second World War he died A that B which C in which D then 2 It was not she took off her dark glasses I realized she was a famous film star A when that B Until that C until when D when then 答案 1 A 2 B 5 But was only the manager A this B that C she D it 答案与简析 选 D 测试 it 可以用作指示代词 指人 当 it 这样用时 所指的是心目 中己知的或上下文中的人或事物 也可用来指婴儿 6 What was the party like Wonderful It s years I enjoyed myself so much A after B before C where D since 答案与简析 选 D 测试 it 用在某固定短语或句型中 如 believe it or not 信不信由你 take it easy 别着急 慢慢来 it is has been since 某人干某事经过了多长一段时间 It seems that 好象 It happens that 碰巧 It looks as if 好象 It is one s turn to do 该轮到谁干 等 又如 Take it Everything will be fine in a day or two A easy B quiet C calm D light 答案是 A 7 It was Shanghai the Communist Party of China was founded A where B that C at which D that where 答案与简析 选 A 测试强调句与定语从句不能混淆 这里是定语从句 若把 Shanghai 的前面加上介词 in 时 就是强调 地点 这时就可以选 B 二 It 精练 40 题 1 Tom s mother kept telling him that he should work harder but didn t help A he B which C she D it 2 I was disappointed with the film I had expected to be much better A that B this C one D it 3 is a fact that English is being accepted as an international language A There B This C That D It 4 As happens I have brought my umbrella with me A it B this C that D such 5 has already been pointed out grammar is not a set of dead rules A As B It D That D This 6 It was seven forty five he finished the work A when B that C when D before 7 I have no idea is so far the airport from here A what B how C it D that 8 Was it because it snowed last night he didn t come A why B that C when D which 9 Does matter if he can t finish the job on time A this B that C he D it 10 Is unnecessary to tell his father everything A that B it C he D this 11 European football is played in 80 countries making the most popular sport in the world A which B this C that D it 12 We are going to hold a meeting tomorrow afternoon Please tell Mr Wang about A this B that C it D the meeting 13 Who is knocking at the door is me A It B That C This D where 14 What time is it now is ten o clock A The time B The o clock C It D That 15 I have seen the baby is very active and lovely A He B She C Who D It 16 He was ill is why he didn t come to the meeting A It B This C That D There 17 is good news that she has passed the entrance examination for Beijing University A That B This C What D It 18 is no doubt that he will succeed in his experiment A It B This C That D There 19 Look someone is coming Who can be A he B she C that man D it 20 I find difficult him to do such work A it of B it for C that of D that for 21 My pen is lost and I can t find anywhere so I must buy A it one B one it C it it D one one 22 We think useless theory without practice A it learning B it learn C that learning D that to learn 23 It is not you who in trouble it is I who in trouble A are am B are is C are are D is is 24 She is already 50 but she doesn t look A like B this C it D such 25 I don t know what was for supper A it B there C that D food 26 Tom s mother kept telling him that he should work harder but didn t help A he B which C she D it 27 The light in the office is still on Oh I forgot A turning it off B turn it off C to turn it off D having turned it off 28 Have you heard the news about Tom No what A is it B it is C are they D they are 29 If you don t know the word why don t you in the dictionary A look at it B look after it C look up it D look it up 30 Is necessary to tell his father everything A it B that C what D he 31 Is possible to fly to the moon in a spaceship A now B man C that D it 32 Is necessary to complete the design before National Day A this B that C he D it 33 Does matter if he can t finish the job on time A this B that C he D it 34 It worried a bit her hair was turning grey A while B that C if D for 35 I don t think possible to master a foreign language without much memory work A this B that C its D it 36 Was it in this pala