语法专项（预习篇）语法专项——☆形容词的比较级☆当我们需要对事物作出比较时，需要用到比较级。
英语中大多数形容词、副词是可以分等级的，一般有三个等级：原级，比较级和最高级。
形容词、副词的本来形式就是形容词的原级。
如：John is a tall boy.两者间进行比较用到形容词比较级。
如：Jim is taller than John.三者或者三者以上进行比较用形容词的最高级。
Mike is the tallest of the three boys.(形容词最高级前一定要加the)1. 形容词比较级：在英语中，两者进行比较，强调"一方比另一方……"，可使用"形容词比较级＋than" 结构比较级的句子结构通常是：什么+ 动词be （am ，is ，are ）+ 形容词比较级+ than（比）+ 什么，如：I’m taller and heavier than you. （我比你更高和更重。
）An elephant is bigger than a tiger. （一只大象比一只老虎更大。
）形容词的比较级是在形容词的基础上变化而来的，它的变化规则是：①一般的直接在词尾加er ，如tall - taller ，strong - stronger ，②以e结尾的，直接加r ，如fine –finer ，③以辅音字母加y结尾的，先改y为i再加er，如funny - funnier④双写最后的字母再加er，如big –bigger，thin –thinner ，除此之外，还有几个特殊的单词，它的比较级和最高级都是不规则的，如：many / much（原形）–more（比较级）–most（最高级）good（原形）–better（比较级）–best（最高级）bad （原形）–worse（比较级）–worst（最高级）far（原形）–further–furthest附加：形容词的最高级变化类似于比较级，只是把词尾的er改成est，如：tall （原形）- taller （比较级）- tallest （最高级）long（原形）- longer（比较级）- longest（最高级）big （原形）- bigger（比较级）- biggest（最高级）2、需要掌握的形容词比较级的形式：tall-taller, short-shorter, old-older, young-younger, strong-stronger, heavy- heavier, long-longer, thin-thinner, big-bigger, small-smaller语法专项预习——一般过去时一、概念表示在的过去某个时间里所发生的动作或存在的状态。
通常在句子里找到表示过去时间的词或词组。
时间状语：yesterday，yesterday morning，yesterday afternoon，yesterday evening，the day before yesterday（前天），last night，last week，last month，last year，a moment ago（刚才），just now（刚才），two days ago，a week ago，in 1990等。
二、动词过去式的构成规律(一)规则动词的过去式1．一般情况下，在动词原形后面加-ed；look→looked play→played start→started visit→visited2．以不发音e结尾的动词，在词尾直接加-d；live→lived use→used3．以“辅音字母+ y”结尾的动词，先将y 改为i ,再加–ed；study→studied, tr y→tried fly→flied4．以重读闭音节（即辅音＋元音＋辅音）或r音节结尾，末尾只有一个辅音字母的动词，要先双写这个辅音字母后，再加–ed。
stop→stopped plan→planned, prefer→preferred(二)不规则动词的过去式1．改变动词中的元音；begin→began drink→drank come→came eat→ate grow→grew run→ran know→knew win→won speak→spoke take→took write→wrote get→got2．变词尾的–d 为–t ；build→built lend→lent send→sent spend→spent bend→bent3．与动词原形一样；cut→cut put→put cost→cost hurt→hurt shut→shut4．变-ay 为-aid (少数动词)；say→said pay→paid lay→l aid5．采用不同词根；sell→sold teach→taught buy→bought6．其他。
am/is→was are→were have/has→had do→did三、加“-ed”后的读音方法1.ed加在清辅音后面读/t/。
finished /-t/ help /-t/ asked /-t/2.ed加在浊辅音或元音结尾的，读/d/。
played /-d/ lived /-d/ enjoyed /-d/3.ed加在/t/或/d/后面，读/id/。
wanted /-tid/ needed /-did/ visited /-tid/四、句型结构：1．在表示某个时间里存在的状态的句子，系动词用过式was，were构成。
如：（1）I was at home yesterday.昨天我在家。
（2）We were in the gym just now. 刚才我们在体育馆。
2．在表示过去某个时间里发生的动作，用动词的过去式构成。
如：I visited my uncle yesterday. 昨天我拜访了我的叔叔。
3．各种句式（1）一般过去时的肯定陈述句：主语＋动词过去式＋宾语或表语。
He worked in Shanghai ten years ago.（2）一般过去时的否定句：a．主语＋didn’t ＋动词原形＋宾语。
(did + not = didn't)He didn't do morning exercises yesterday.b．主语＋wasn’t/weren’t ＋表语。
(was + not = wasn't were + not = weren't) He wasn't an English teacher ten years ago.（3）一般过去时的一般疑问句：a．Did ＋主语＋动词原形＋宾语？Did you study English in 1990 ?（肯定回答：Yes, I did. 否定回答：No，I didn’t.）b．Was/Were + 主语＋表语？Was he a pupil five years ago ?(肯定回答：Yes, he was. 否定回答：No, he wasn’t.)（4）一般过去时的特殊疑问句：a．特殊疑问词＋did + 主语＋动词原形＋宾语？Where did your parents live five years ago？What did you do last Sunday？b．特殊疑问词＋were/was ＋表语？Who was at the zoo yesterday?五、句式变化（一）一般过去时的一般疑问句1．把was, were放在句首，其余位置不变。
由Was…？引导的一般疑问句，肯定答为：Yes，…was. 否定回答为：No，…. wasn’t. 由Were…？引导的一般疑问句，肯定回答为：Yes，… were. 否定回答为：No，… weren’t.如：（1）I was born in Shanghai. →Were you born in Shanghai?→Yes, I was. (肯定回答) →No, I wasn’t. (否定回答)（2）They were in Li Yan’s home last night. →Were they in Li Yan’s home last night?→Yes, they were. (肯定回答) →No, they weren’t. (否定回答)2．在行为动词的句子中，要用助动词词did来引导，其余的语序不变。
要注意的是，要把行为动词的过去式改为原形。
肯定回答为：Yes, …did. 否定回答：No, …didn’t.如：John played computer games last night.→Did John play computer games last night?→Yes, he did. (肯定回答) →No, he didn’t. (否定回答)（二）一般过去时的否定句1．在表示过去存在的状态的句子中，相接在was, were的后面加上not。
如：（1）He was in the park the day before yesterday.→He was not in the park the day before yesterday.(2)We were busy last week.→We were not busy last week.2．在表示过去的时间发生的动作的句子中，要在行为动词的前面加助动词didn’t.然后把过去式的行为动词改为动词原形。
即：didn’t + 动词原形。
如：（1）She played the violin last night.→She didn’t play the violin last night.(2)They swam in the lake yesterday.→They didn’t swim in the lake yesterday.(三)、一般过去式的特殊疑问句1.What did …?（主要是询问过去发生了什么事情，注意要把过去式改为动词原形。
）We ate Chinese food last night.→What did we eat last night?2.Where did ?( 主要是询问过去事情发生的地方。
)They sang and dance in the music room yesterday morning.→Where did they sing and dance yesterday morning?3.Who + 动词过去式…?( 主要是询问过去事情发生的人物。
)Mike and Tom climbed mountains last weekend.→Who climbed mountains last weekend?六．小结. 过去式的肯定、否定、疑问及简短回答1. 过去式的肯定、否定、疑问及简短回答的形式可表示如下：肯定句：I (He, She, We, You, They) went there by bus.否定句：I (He, She, We, You, They) didn't go there by bus.疑问句：Did I (he, she, we, you ,they) go the by bus?简短回答：Yes, I (He, She, We, You, They) did.No, I (He, She, We, You, They) didn't.2. 动词be的肯定、否定、疑问及简短回答形式如下：肯定句：I (He, She) was there.We (You, They) were there.否定句：I (He, She) wasn't there.We (You, They) weren't there疑问句：Was I (he, she) there?Were we (you, they) there?简短回答：No, I (he, she) wasn't.we (you, they) weren't.。