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
Alula-Fartak Trench
amphids
angina epiglottidea
Armen-
array expression
auto-covariance function
Bacillus coli communis
baytex
beam satellite antenna
behzad
bioassay parameter
broomweeds
Cambrils
Carex sinodissitiflora
cisterna cruralis
compressor rated point
correction of chroma amplitude
crossed-grid matrix
Cuyuni River
def(a)ecation
dielectric heat
dihydrovitamin
dikepond system
directrix of conic
disastrous accident
emergency flooding
enterprise Java bean
Eolie, Isole
erddig
excited field speaker
femmephobic
friberg
full load operation
fully loaded rotor
galtonia candicanss
green material
grumbliest
hard timess
Harding R.
Homerical
Ihlienworth
ill-dressed
importunately
inherent delay angle
intensity of absorption bands
international commodity agreement
intrasatellite switching
jeffcote
kick-started
lemon-yellows
lithium hydroxide monohydrate
loudmouth
ludet
Luvungi
marine centrifugal type refrigeration compressor unit
Masbate
meringues
Michelia alba concrete
mistbelt
motleyness
mullaly
neutron-emitting re-action
No-methemogtobin
non-dissipative interaction
nymphalids
Oriels
Passenger Ship Safety Certificate Survey
pentameral
persral
pervious
philonotis setschuanica (c.m(u)ll.) par.
picea
poldervaartite
price per kilowatt-hour
pure statistical estimation
random-access device
readvertisement
receiving surface (of photometer head)
releasing of relay
rod drive screw
sandscapes
saqqarahs
scope of ecology
scoutmasters
shift to right
slow-foot
sporogonies
three critical conditions of neonatal tetanus.
undefined operation code
under no conditions
undevilish
vasopressors
vogon
vorticose
white tumors
whole body X-irradiation
wingings
wire grating
Xiphodontidae
yamanaka shigure (japan)
zero energy reactor