内容正文:
专题04 重点语法
【知识梳理】
1. Be动词的用法
• 我用am,你用are,is用于他、她、它,单数用is,复数就用are。
• 含be动词的陈述句变否定句在be后加not,变一般疑问句将be提前。
• 一般疑问句的肯定回答:Yes, 人称代词+ be;否定回答:No, 人称代词+be + not。
如:---They are teachers. ---They are not teachers.
---Are they teachers? ---Yes, they are./ No, they aren’t.
2. 不定冠词、定冠词和and的用法
(1)不定冠词a, an的用法
a /an 都表示“一,一个”,a 用在以辅音音素开头的单词前,如:a book; a desk; an 用在以元音音素开头的单词前,如:an apple / an orange/ an English book;/ an English boy/ an old man;/an actor/ an English teacher/ an office worker.
(2)the是定冠词,表特指,单复数前面都可用
• We are in the same class.
• The girl in a pink skirt is Jane.
• Where is the book?
• This isn’t my bike. The blue one is mine.
(3) and的用法
• 数字相加看做单数:Two and three is five.
• 颜色相加也是单数: Black and white is gray.
• 人和事物相加是复数:Lucy and Lily are sisters. The pen and the eraser are Jane’s.
3. 可数名词单数变复数
(1)规则变化
① 一般在名词词尾加-s,如:car---cars; photo---photos; toy---toys; boy---boys
② 以s, x, ch, sh结尾的词,在词尾加--es,如:box---boxes; bus--buses
③ 以辅音字母+y结尾,变y为i再加es,如:baby--babies; family--families
④ 以fe结尾,变fe为v再加es,如:knife--- knives
(2)不规则变化
如:foot---feet; man---men; woman---women; snowman---snowmen;
(3)集体名词:people, clothes, police, family
(4)成双出现的名词:shoes, pants(trousers), gloves, eyes, ears
6. 一词多义
4. 动词原形和动词第三人称单数形式
(1)主语是第三人称单数形式(he、she、it;单一的人;单一的名字;单一的事物),动词要用单三形式。实义动词变第三人称单数的规则:
① 一般情况直接加“s”,如:come---comes,meet---meets
② 动词以o,s,sh,ch, x结尾,加“es”,如:do--does; go--goes; teach--teaches
③ 以辅音字母+y结尾,变y为i,再加es, 如:study--studies, fly--flies, try--tries
④ 特殊情况:have--has
(2)句型转换
① 当主语为第三人称单数:变否定句时,在动词前加doesn’t, 动词现原形;变一般疑问句时,在句首加does,动词现原形。
一般疑问句的肯定回答:Yes, 人称代词+does;否定回答:No, 人称代词+doesn’t.
如:She has small eyes.
---She doesn’t have small eyes.
---Does she have small eyes?
---Yes, she does. /No, she doesn’t.
② 当主语为第一、第二人称变否定句,在动词前加don’t,变一般疑问句,在句首加do,肯定回答:Yes, 人称代词+do;否定回答:No,人称代词+don’t.
They have small eyes.
---They don’t have small eyes.
--- Do they have small eyes?
---Yes, they do. / No, they don’t.
5. 表示所属关系
(1)名词性物主代词=形容词性物主代词+名词
形容词性物主代词 my your his her our their it