时间:2019-02-01 作者:英语课 分类:英文语法词汇


英语课
特征
1)情态动词(modal verb)本身有词义,表示说话人的语气或情态,但词义不完全,不能单独用作谓语动词,一般只能和动词原形一起构成谓语动词。
2)情态动词所表示的情态有:命令、允诺、请求、拒绝、愿望、愿意、义务、必要、可能、能力、敢于、需要等。
3)情态动词(ought除外)和助动词shall,will,should,would一样,后面的动词不定式一般皆不带。
形式变化
1)没有人称和数的变化,第三人称单数的现在时也无变化。如:
I can We can
You can You can
He
They can
She can
It 
2)有些情态动词有过去式,有少数过去式和它的原形相同。
a)有过去式的情态动词有:
may —— would
can ―― could
may―― night
shall —— should
have to —— had to
b)过去式不变的情态动词有:
must — must (或had to)
ought to — ought to
need———need
dare — dare(亦可用dared)
3)大多数情态动词后面可用动词的进行式、完成式和被动形式,如:can(may,must)be doing,can(may,must) have done,can(may,must)be done等。
否定式
情态动词和助动词一样,后面可直接跟否定词not。现将情态动词的否定式及其否定式的简略式(简略式用于口语中)列举如下:
shall not——shan't [FB:nt]
will not———won't [wEunt]
can not—can't [kB:nt]
must not—mustn't [5mQsnt]
should not—— shouldn't
would not—— wouldn't
could not—— couldn't
dare not— daren't [dZEnt]
need not—— needn't

在疑问句中的用法
情态动词在疑问句中的用法和助动词相同。如:
May I ask you a question? 我可以问你一个问题吗?
Can you let me use your dictionary for a minute? 你能把字典借我用一会儿吗?
Would you like to visit the heavy machinery plant? 你想参观重型机器厂吗?
注意have to在疑问句中的位置。如:
Do you have to go out today? 你今天一定得出去吗?
Does he have to finish the work tomorrow? 他明天非做完这项工作不可吗?


学英语单词
a pair of drawers
Abernethy biscuit
administrative procedure
alkyl phenol resin
atmocautery
bag-reef
baked porcelain root
ballistic missile early warning system
bicircular surface
bone tumors resulting from radiation
braces aback
clicketing
common comfrey
computer and cyber law
concentration-camp
consumers'association
container carrying car
crucibleless technique
curkle
Defibrol
defrizzes
delphinus
distant reading thermometer
draftspersons
driver's seat
duration of risk on ship
early retirement
electrical bandwidth
exploratory sampling
foramina nasalia
fractional lood
globus abdominalis
green light
habit formation principle
heating grid
high cistern
hour wheel seating
immediate order
in one piece
increasing production and saving
incremental control
inducing current
intercontinental sea
issuing room
Kryry
lacquer
lactone isomerism
Lanella
limited disclosure
logogriph
Los Ramones
Lysimachia sciadantha
main spindle
maintenance ration
mark zone
metalegal
mosburg (germany)
mucotab
museumplein
newspaper room
Næsby
on the commission
one-breasted
operating ampere-turn
opposite test
orthogonal complement space
paraffinhydrocarbon
parent-investor
parmelia submutata
petnidan
pittled
price per kilowatt-hour
productivity gain
pseudospiral
ready to wear store
regulating variable
reversal of control
rhamphoid cusp
right-handed machine
scattering angular distribution
secondary loess
shmacked
Sikan
sir walter
sixteener
special purpose check
spreadin'
stable programming
steel pit
subenergetic phonation
SYCHIDAE
sympathicopathy
tail-rhyme
talk sth over sb
ticks someone off
tractabilities
Tricholoma flavovirens
troump
tyloperla sauteri
vins de table
wet take-off thrust
wooden handle