2020届高考英语Unit3-Unit4第一轮总复习讲稿. 重点精讲A. 重点单词讲解 consider: 作“考虑；细想”解时，后接名词、-ing形式或宾语从句。作“当作；当成；认为”解时，后接含有as的介词短语或to be复合宾语。Eg. Have you considered changing your job?We considered him (to be/as) our best friend.注意：consider后接it作形式宾语的情况：I consider it a great honor. 我认为这是极大的荣幸。= I consider that it is a great honor. I consider it my duty to tell the truth. 我认为有责任来说明真相。 They considered Mr. Li to have built the data bank. 他们认为是李先生建立了这个数据库。注：consider不能用于进行时态。比如：不能说 He is considering. ,而应该说：He considers. 。 means: 作“方法；手段；工具；能力”解时，单数和复数相同。means of transportationThere are (is) no means of getting there.没有办法去那里。 A train is a means of transportation.【相关归纳】（1）by all means可以；当然行；没问题；务必；尽一切办法Eg. Do you mind if I have a look? By all means.By all means, I would like to see you this evening!无论如何，（2）by no means决不；一点也不Eg. Am I wrong? No, by no means.（3）by means of用；依靠Eg. We can express our feelings by means of words.（4）by this means通过这种方式 experience: （1）作“（一次）经历；体验”解时，是可数名词；作“经验”解时，是不可数名词。 （2）作及物动词时，意为“经历；经受；遭受；体验” popular: 作形容词，主要义项有：流行的；受欢迎的；受喜爱的；通俗的；大众的注意：表示“受某人的欢迎”，只能用be popular with sb.不能用be popular by sb.Eg. She is very popular with the students. however: 主要有两个义项：（1）然而，可是；仍然。作此义项时，其显著特点是与逗号连用。（2）无论多么；不管多么。通常与形容词或副词连用，引导让步状语从句。Eg. However carefully I explained, she still didnt understand. once:（1）连词，主要义项为：一就；一旦；当时候。（2）副词，主要义项为：一次；曾经；曾；根本。注：once引导的状语从句中，要用一般现在时来表示将来的动作。Eg. Once you show any fear, he will attack you.【相关归纳】（1）all at once突然；骤然；忽然；一起；同时Eg. All at once she lost her temper.I cant do everything all at once youll have to be patient.（2）at once立即，马上；同时（3）once more(=once again)再一次；再次（4）once or twice一两次；几次（5）once in a while偶尔（6）once upon a time从前（7）Once bitten, twice shy.一朝被蛇咬，十年怕井绳。 protect: 主要义项有：保护；防护。常见结构：protect sb./sth. from; protect sb. againstEg. He was wearing sun-glasses to protect his eyes from the sun.Its soldiers duty to protect our country against attack. 查漏补缺 get close to nature 接近大自然 (1)close adj. 1.近的,接近的(+to) 2. (关系)密切的,亲密的 3. (尤指比赛)势均力敌的adv. 1.接近,靠近地(+to) 2.紧密地,紧紧地 e.g. His house is close to the factory. 他家靠近该厂。 She is a close friend of theirs. 她是他们的挚友。 She sits close to her mother. 她挨着她妈妈坐着。 (2)nature n. 自然(界);本质,天性 nature解释为“大自然，自然界”时前面不加冠词 e.g. You must know the laws of nature. 你必须了解自然界的法则。Habit is second nature. 习惯成自然。【固定搭配】in nature在自然界 against nature违背自然 (规律) separate在此句中用作形容词，意思是“单独的，各自的”。e.g. The children sleep in separate beds. 孩子们是分床睡的。用作动词时，通常是 separate sth. / sb. from辨析separate，divide 这两个词都可用作动词，意思是“分开”。但有一定的不同。separate通常指把原来结合在一起，混合在一起的分开或隔离。divide着重指把整体分成若干部分。 e.g. You should separate the good apples from the bad ones. 你应该把好苹果和坏苹果分开。 The house is divided into four parts. 这间房屋分成四部分。 protectfrom保护不受（伤害）/ preventfrom阻止做某事 We wear sunglasses to protect our eyes from the sun. / We wear sunglasses to prevent the sun form hurting our eyes. as with=as its the same with.正如一样 As with drawing a picture, you should be patient and careful in doing this job. 正如画画一样，在做这件事时，你应该耐心细致。 与feet相关的短语：get on ones feet 站住脚，站起来；struggle to ones feet 挣扎着站起来；rise to ones feet 站起，起身；jump to ones feet 跳起来；take to ones feet 走开；bring sb to ones feetB. 重点短语 at the same time：同时；一齐；但是；然而；不过【相关归纳】（1）at all times总是；随时；永远（2）at the best of times即使在最好的情况下Eg. Hes never very happy at the best of timeshell be much worse now!（3）at a time每次；逐一；依次（4）at times有时；间或 see sb. off为送行；送别；赶走；驱逐（某人）；（在游戏、战斗等活动中）打败；击败 not at all：可以用在否定句中，意思是“根本不，一点也不”；也可单独使用，特别是在答语中，意思是“一点也不，没关系，不用谢”。【相关归纳】at all到底；真的；竟然。可用于肯定句及疑问句，起强调作用，常带有较强的感情色彩。 find out了解（情况）；打听；发现；查出（坏人）；识破C. 必背句型 reason结构：reason后接定语从句，如果reason在定语从句中作宾语，定语从句应由关系代词that（可省略）引导，否则应由why引导。Eg. Do you know the reason why he was absent today?He was absent today. The reason (that) he gave was that his mother was ill.【相关归纳】（1）“the reason for+名词/动名词”表示“的理由/原因”Eg. Do you know the reason for his being absent today?（2）汉语中的“原因是因为”，在英语中要用“The reason is that”来表达，不可以用“The reason is because”,也就是说，reason后的表语从句应由that引导。Eg. The reason why he was absent today was that he was ill. unless引导的状语从句（1）注意unless的否定含义：unless=if not;Eg. Well go for a picnic this weekend unless it rains.（2）注意unless引导的状语从句中用一般现在时表示将来的动作或状态。Eg. You wont get paid for time off unless you have a doctors note.3. so的替代作用：so表示“这样，如此”时，可用来替代整个句子或某一情况的全部，常与think, expect, hope, believe, suppose, imagine, guess等动词及形容词afraid连用。【相关归纳】把suppose so, think so, imagine so等结构变为否定式有两种方法；可用动词的否定结构，或用not替代so。 must的推测性用法：must可以用于对肯定或有把握的事情或情况表示推测，意思是“必定，准是，很可能”。（1）must +do表示对现在情况的推测。（2）must +have done表示对过去情况的推测。（3）must +be doing表示对正在发生的动作或将要发生的动作的推测。【相关归纳】（1）表示否定推测只能用cant，不能用mustnt。（2）情态动词can和must表示推测时，其反意疑问句不能用情态动词，必须去掉情态动词之后在句子本来意义的基础上进行反问。如：He must have seen the film.可以理解为He has seen the film.,所以反意疑问句用hasnt he? He must have seen the film yesterday.可理解为He saw the film