2021年高考英语二轮复习学案情态动词和虚拟语气考点讲解含解析

情态动词和虚拟语气
第一部分、情态动词
一、can/could与be
able
to
1．can/could用来表示“一般能力”；be
able
to有多种时态，且用来表示在特定条件下的“具体能力”。如：
My
grandma
is
over
seventy，but
she
can
still
read
without
glasses.
They
will
be
able
to
tell
you
the
news
soon.
He
was
able
to
flee
Europe
before
the
war
broke
out.
2．表示允许可用can或could，与may/might意义接近。could可用于现在时，只是语气更加委婉、客气，回答时则一般要用can而不用could。
—Could
I
have
the
television
on?
—Yes，you
can./No，you
can't.
二、may与might
1．表示允许，意为“可以，许可”，用法基本上同can与could。如：
May
I
use
your
bicycle?
2．表示可能性，意为“也许，可能”。如：
According
to
the
weather
forecast,
it
may
rain
tomorrow.
3．may可以放在句首，表示祝愿。如：
May
good
luck
be
yours!
三、must与have
to
1．must用来表示说话人的主观看法；have
to表示客观的需要，强调外界压力，不得已而为之。如：
He
said
that
they
must
work
hard。
他说他们必须努力工作。(主观上要做这件事)
My
brother
was
ill,
so
I
had
to
call
the
doctor
in
the
middle
of
the
night.
我弟弟生病了，我只得半夜里把医生请来。(客观上需要做这件事)
2．表示“不必”，须用don't
have
to或needn't。must的否定式表示“禁止，绝对不可”。如：
You
don't
have
to
tell
him
about
it.
你不必告诉他那件事。
You
mustn't
tell
him
about
it.
你绝不能告诉他那件事。
—Must
we
do
it
now?
我们必须现在做吗？
—No,
you
needn't.
不，你们不必。
四、shall
1．用于第一、第三人称的疑问句中，用来征求对方的意见或请求指示。如：
What
shall
he
do
next?
他下一步干什么呢？
2．用于第二、第三人称的陈述句中，表示说话人的意愿，有“命令、警告、允诺、威胁、强制”等意思。如：
He
shall
stay
in
bed.
他必须躺在床上。
You
shall
have
it
back
next
week.
下周一定还你。
He
says
he
won't
go,
but
I
say
he
shall.
他说他不去，但我说他必须去。
五、will与would
1．will用于各种人称，表示“意志、意愿”或“决心”等。如：
If
you
will
keep
your
watch
half
an
hour
slow,
it
is
hardly
surprising
that
you
are
late
for
your
appointments.
如果你想要让你的表慢半个小时，你约会时迟到就不足为怪了。
2．will表示习惯性的动作，有“总是，惯于”的含义。如：
An
Englishman
will
usually
show
you
the
way
in
the
street.
英国人通常是会在街上给你指路的。
3．would可表示过去反复发生的动作。如：
On
Sundays
he
would
get
up
early
and
go
fishing.
星期天他总是早起去钓鱼。
六、should与ought
to
1．should表示“建议”或“劝告”，有“应该”之意。如：
You
should
learn
from
each
other.
2．ought
to表示根据某种义务或必要“应当”做某事。如：
Everyone
ought
to
obey
the
traffic
regulations.
3．should和ought
to也可用来表示推测，意为“想必会……”。如：
—When
can
I
come
for
the
photos?
I
need
them
tomorrow
afternoon.
—They
should
be
ready
by
12?00.
七、情态动词表示推测
1．can用于肯定句中表示客观的可能性，意为“有时会”；用于疑问句中可以表示推测，意为“可能”，有时表示一种惊讶的语气；用于否定句中也可以表示推测，can't意为“不可能”，语气很强烈。
It
is
usually
warm
in
my
hometown
in
March,
but
it
can
be
rather
cold
sometimes.
我的家乡在三月份通常很暖和，但有时候也会相当冷。
Mr.
Bush
is
on
time
for
everything.
How
can
it
be
that
he
was
late
for
the
meeting?
布什先生做什么事情都很准时，他怎么可能开会迟到呢？
—Let's
visit
Tom
together,
Stephen.
—There's
no
need
to
do
so.
He
can't
be
at
home,
because
I
saw
him
board
the
flight
to
Beijing
this
morning.
——Stephen，咱们一起拜访汤姆吧。
——没必要这样做。他一定不在家，因为今天早晨我看见他登上了飞往北京的航班。
2．may/might用于肯定句中可以用来表示不十分肯定的推测，意为“有可能”；用于否定句中也可以表示推测，may
not意为“可能不”，表示一种不太确定的语气。
The
traffic
is
heavy
these
days.
I
might
arrive
a
bit
late,
so
could
you
save
me
a
place?
这些天交通很繁忙，我可能会来晚一点，请你帮我保留个位置好吗？
3．must表示推测时只能用于肯定句中，意为“一定，必定”，表示十分肯定的语气(在疑问句中或否定句中要用can/could)。
—It's
the
office!
So
you
must
know
eating
is
not
allowed
here.
—Oh,
sorry.
——这是办公室！所以你一定知道这里不许吃东西。
——噢，对不起。
4．should用来表示推测时意为“应该”，即含有“按道理来说应当如此”的意思。
There
shouldn't
be
any
difficulty
about
passing
the
road
test
since
you
have
practiced
a
lot
in
the
driving
school.
因为你在驾校训练了这么多，通过路考应该没什么困难。
八、“情态动词＋have
done”结构
1．should/ought
to＋have
done，表示“过去本应该做而(实际)没有做的事情”，含有责备或遗憾的语气，意为“本应该……”。其否定形式为“should
not/ought
not
to
have＋done”，表示某种行为本不该发生但实际上发生了。
I
shouldn't
have
watched
that
movie—it'll
give
me
horrible
dreams.
我本不应该看那部电影——它会令我做噩梦。
You
ought
to
have
come
to
the
party
yesterday,
but
why
didn't
you
come?
昨天你本来应该参加聚会的，可是你为什么不来？
2．must＋have
done，用于肯定句，表示“过去一定做过某事”，表示一种很有把握的推测。注意，对过去发生的情况的否定推测常用“can't/couldn't＋have
done”表示。
—Ye
Shiwen
won
two
gold
medals
in
London
Olympic
Games.
—She
must
have
gone
through
tough
training.
——叶诗文在伦敦奥运会获得了两枚金牌。
——她肯定受到严格的训练。
—Do
you
know
where
David
is?
I
couldn't
find
him
anywhere.
—Well.
He
can't
have
gone
far—his
coat's
still
here.
——你知道大卫在哪里吗？我到处找不到他。
——大卫的上衣还在这里，因此他肯定没走远。
3．needn't＋have
done，表示“过去没有必要做某事，但实际上做了某事”。
Mark
needn't
have
hurried.
After
driving
at
top
speed,
he
arrived
half
an
hour
early.
马克本没必要那么匆忙。他以最快速度开车，结果早到了半个小时。
4．may/might＋have
done，表示对过去情况的一种不太有把握的可能性的推测，表示“可能已做了某事……”，否定句表示“可能还没有……”。
Sorry,
I'm
late.
I
might
have
turned
off
the
alarm
clock
and
gone
back
to
sleep
again.
对不起，我迟到了。我可能把闹钟关掉后又睡着了。
5．could＋have
done表示“过去本来可以做某事，但实际上没有做”；can/could＋have
done表示“过去可能做了某件事”。
I
could
have
saved
the
poor
rabbit,
but
I
didn't
have
the
right
drugs
with
me
at
that
moment.
我本来可以拯救那只可怜的兔子的，可是我当时没有合适的药品。
第二部分、虚拟语气
一、虚拟语气在虚拟条件句中的用法
虚拟情况
从句谓语
主句谓语
例句
与现在事
实相反
过去式
(be用were)
would/
should/
could/might
do
If
he
were
here,
he
might
be
able
to
help.
What
would
you
do
if
you
were
in
his
place？
与过去事实相反
had
done
would/
should/
could/might
have
done
If
I
had
started
a
little
earlier,
I
would
have
caught
the
train.
I
could
have
done
it
better
if
I
had
been
more
careful.
与将来事实相反
过去式
were
to
do/
should
do
would/
should/
could/might
do
If
I
were
to
do
it,
I
would
do
it
in
a
different
way.
I
would
certainly
go
if
I
had
time.
1.在具体运用中，条件从句中有时可省略if而采用倒装结构。如：
Had
it
not
been
for
your
help,
we
wouldn't
have
achieved
so
much.
2．介词without/but
for、连词but、副词otherwise常用来表示某种假设条件。如：
I
wouldn't
have
made
such
rapid
progress
without
your
help.
3．有时候从句动作和主句动作发生的时间不一致，这时谓语动词的形式要根据各自的时间来调整。如：
If
the
weather
had
been
more
favourable,
the
crops
would
be
growing
still
better.
二、“should＋动词原形”表示的虚拟语气
这一类型常见词有“一坚持(insist)、二命令(order,
command)、三建议(advise,
suggest,
propose)、四要求(request,
require,
demand,
desire)”。以上词及其派生名词所接的名词性从句都使用“(should＋)动词原形”的虚拟语气。
①Jane's
pale
face
suggested
that
she
was
ill,
and
her
mother
suggested
that
she(should)
have
a
medical
examination.
简苍白的脸色表明她病了，她母亲建议她去检查身体。
②She
insisted
that
the
man
had
stolen
her
car
and
that
he(should)
be
sent
to
prison.
她坚持说那个男人偷了她的车，并坚决要求他坐牢。
三、特殊句式中的虚拟语气
If
only/It's
(high)
time
(that)．..
wish/would
rather/as
if等固定句式要求用相应的虚拟语气表达形式。
①I
wish
I
could
fly.
真希望我能飞。
②I
would
rather
you
came
tomorrow.
我宁愿你明天来。
③If
only
I
had
taken
your
advice!
要是听从了你的建议该多好啊！
高频考点一、考查情态动词
例1．（2018·北京卷）In
today’s
information
age,
the
loss
of
data
_________
cause
serious
problems
for
a
company.
A.
need
B.
should
C.
can
D.
must
【答案】C
【解析】考查情态动词。句意：在今天的信息时代，数据的丢失有时会对一个公司造成严重的问题。数据丢失造成严重问题是客观上会发生的情况，即“客观可能性”，故该空应用情态动词can。C选项正确。其余情态动词均没有该用法。need需要；should应该，竟然；must必须，肯定。
【变式探究】—Can’t
you
stay
a
little
longer?
—It’s
getting
late.
I
really
_____go
now,
My
daughter
is
home
alone.
A
.may
B
.can
C
.
must
D
.dare
【答案】C
【解析】句意：——你不能再多待会儿吗?——很晚了，我必须得走了。我女儿一个人在家。A.
may可能，可以，也许；B.
can能，会；C.
must必须，必然要，必定会；D.
dare敢，胆敢。结合句意，故选C。
【变式探究】________
I
have
a
word
with
you?
It
won’t
take
long.
A.
Can
B.
Must
C.
Shall
D.
Should
【答案】A
【解析】本题考察的是情态动词基本意义辨析。Can能够，可能；must必须，一定；非得；shall将要；should应该；句意：我可以和你谈谈吗？不会花很多时间的。根据句意可知本题使用can
I…？表示询问对方是否允许。如：Can
I
use
your
dictionary?我可以使用你的字典吗？故A正确。
高频考点二、考查情态动词的用法
例2.
（2018·天津卷）
I
can't
find
my
purse.
I___________
it
in
the
supermarket
yesterday,
but
I'm
not
sure.
A.
should
leave
B.
must
have
left
C.
might
leave
D.
could
have
left
【答案】D
【解析】考查情态动词表推测。句意：我不能找到我的钱包了，昨天我有可能把它落到超市了，但我不确定。根据句中时间状语yesterday可知，是对过去事情的推测，故用情态动词+
have
done，再根据后句but
I’m
not
sure.可知，此推测为不能肯定的推测，故用情态动词could，表示“可能”。故选D。
【变式探究】（2017?天津）My
room
is
a
mess,
but
I
__________clean
it
before
I
go
out
tonight.
I
can
do
it
in
the
morning.
A.
daren’t
B.
shouldn’t
C.
needn’t
D.
mustn’t
【答案】C
【解析】
句意：我的房间很乱，但是在今晚我出去之前不需要打扫，我可以明天早晨再打扫。A.不敢；B.不应该；C不需要；D.不许。根据句意，故选C。
【变式探究】Why
didn't
you
tell
me
about
your
trouble
last
week？If
you
________(tell)me，I
could
have
helped.
【答案】had
told　
【解析】句意：上个星期你为什么不告诉我你的麻烦事？如果你告诉我了，我就能帮你。根据句意和相关信息判断，条件句表示与过去事实相反的假设，此时从句用过去完成时，主句谓语用“情态动词＋have
done”形式。
【变式探究】I
______
have
worried
before
I
came
to
the
new
school,
for
my
classmates
here
are
very
friendly
to
me.
A.
mightn’t
B.
mustn’t
C.
needn’t
D.
couldn’t
【答案】C
【解析】句意：我来新学校之前本没有必要担心，因为在这里我的同学对我非常友好。needn’t
have
done本没有必要做某事，表示实际上已经做了某事。根据句意可知选C。
高频考点三、考查虚拟语气
例3．(2019·天津卷)The
workers
were
not
better
organized,
otherwise
they
________
the
task
in
half
the
time.
A．accomplished
B．had
accomplished
C．would
accomplish
D．would
have
accomplished
【答案】D　
【解析】考查虚拟语气。句意：工人们没有被组织好，否则的话他们会用那一半的时间完成任务的。此处otherwise表达了一种含蓄虚拟；otherwise前的内容所述的是过去的事实，相当于if引导的条件状语从句“If
the
workers
had
been
better
organized”，因此后半部分应用“主语＋would
have
done
sth.”的结构。故选D。
【举一反三】【2018·江苏】It’s?strange?that?he?_______
have?taken?the?books?without?the?owner’s?permission.
A.
would
B.
should
C.
could
D.
might
【答案】B
【解析】考查虚拟语气。句意：真奇怪，他竟然没有主人的允许就拿走了这些书。在句型”It
is
important/necessary/strange/impossible/natural
that...”中，其中由that引导的主语从句通常用“should+动词原形”这样的虚拟语气，其中的should可以省略。故选B。
【变式探究】（2017·北京）If
the
new
safety
system
_______
to
use,
the
accident
would
never
have
happened.
A.
had
been
put
B.
were
put
C.
should
be
put
D.
would
be
put
【答案】A
【解析】句意：如果这个新的安全系统被投入使用过的话，这个事故就不会发生了。根据主句确定是对过去情况的虚拟，所以从句谓语用had
done形式，此外根据句意可知是被动，用被动语态，故A项是正确的。
【变式探究】________(have)the
governments
and
scientists
not
worked
together，AIDS?related
deaths
would
not
have
fallen
since
their
highest
in
2005.
【答案】Had　
【解析】句意：如果政府和科学家不共同努力，与艾滋病相关的死亡就不会从2005年的最高点下降。这是一个省略了从属连词if的虚拟语气句，使用了倒装句式。根据主句的would
not
have
fallen可知，这里是表示过去的虚拟语气，所以用had。
【变式探究】Without
his
wartime
experiences,
Hemingway____
his
famous
novel
A
Farewell
to
Arms.
A.didn’t
write
B.
hadn’t
written
C.
wouldn’t
write
D.
wouldn’t
have
written
【答案】D
【解析】句意：没有他战时的经验，海明威就不可能写出著名的小说永别了武器。根据without
his
wartime
experience没有战时的经历，可知表示对于过去的否定猜测，故主句用would
have
done，因此选D项。
1．(2019·天津卷)The
workers
were
not
better
organized,
otherwise
they
________
the
task
in
half
the
time.
A．accomplished
B．had
accomplished
C．would
accomplish
D．would
have
accomplished
【答案】D　
【解析】考查虚拟语气。句意：工人们没有被组织好，否则的话他们会用那一半的时间完成任务的。此处otherwise表达了一种含蓄虚拟；otherwise前的内容所述的是过去的事实，相当于if引导的条件状语从句“If
the
workers
had
been
better
organized”，因此后半部分应用“主语＋would
have
done
sth.”的结构。故选D。
2．(2019·江苏卷)What
a
pity!
You
missed
the
sightseeing,
or
we
________
a
good
time
together.
A．had
B．will
have
C．would
have
had
D．had
had
【答案】C　
【解析】考查虚拟语气。句意：多么遗憾！你错过了这次游览。否则，我们就可以一起度过一段愉快的时光。根据关键词or可知，这里表示与过去的事实相反，谓语动词应用would/could/should/might＋have
done。
1.【2018·江苏】
There
is
a
good
social
life
in
the
village,
and
I
wish
I
_______
a
second
chance
to
become
more
involved.
A.
had
B.
will
have
C.
would
have
had
D.
have
had
【答案】A
【解析】考查虚拟语气。句意：在这个村里有很好的社交生活，并且我希望我再有机会去更多的参与。本题考查wish引导的宾语从句，表示与现在事实相反的愿望，所以从句用一般过去时。故选A。
2.【2018·江苏】It’s?strange?that?he?_______
have?taken?the?books?without?the?owner’s?permission.
A.
would
B.
should
C.
could
D.
might
【答案】B
【解析】考查虚拟语气。句意：真奇怪，他竟然没有主人的允许就拿走了这些书。在句型”It
is
important/necessary/strange/impossible/natural
that...”中，其中由that引导的主语从句通常用“should+动词原形”这样的虚拟语气，其中的should可以省略。故选B。
3.（2018·天津卷）
I
can't
find
my
purse.
I___________
it
in
the
supermarket
yesterday,
but
I'm
not
sure.
A.
should
leave
B.
must
have
left
C.
might
leave
D.
could
have
left
【答案】D
【解析】考查情态动词表推测。句意：我不能找到我的钱包了，昨天我有可能把它落到超市了，但我不确定。根据句中时间状语yesterday可知，是对过去事情的推测，故用情态动词+
have
done，再根据后句but
I’m
not
sure.可知，此推测为不能肯定的推测，故用情态动词could，表示“可能”。故选D。
4.（2018·北京卷）In
today’s
information
age,
the
loss
of
data
_________
cause
serious
problems
for
a
company.
A.
need
B.
should
C.
can
D.
must
【答案】C
【解析】考查情态动词。句意：在今天的信息时代，数据的丢失有时会对一个公司造成严重的问题。数据丢失造成严重问题是客观上会发生的情况，即“客观可能性”，故该空应用情态动词can。C选项正确。其余情态动词均没有该用法。need需要；should应该，竟然；must必须，肯定。
5.（2018·北京卷）They
might
have
found
a
better
hotel
if
they
_________
a
few
more
kilometers.
A.
drove
B.
would
drive
C.
were
to
drive
D.
had
driven
【答案】D
【解析】考查虚拟语气。句意：如果他们多开几公里的话，他们也许会找到一个更好的旅馆。由“they
might
have
found
a
better
hotel”可知，该句是表示对过去的虚拟。if
____
a
few
more
kilometers是条件句部分，表示对过去的虚拟，条件句部分要用过去完成时态，故D选项正确。
1．（2017·北京）Samuel,
the
tallest
boy
in
our
class,
______
easily
reach
the
books
on
the
top
shelf.
A.
must
B.
should
C.
can
D.
need
【答案】C
【解析】A.
must
必须
B.
should
应该
C.
can
能
D.
need
需要。句意:Samuel，我班最高的男生，能很轻松地够着书架顶上的书，此处需要一个表示能力的词，故用can，答案为C。
2．（2017?天津）My
room
is
a
mess,
but
I
__________clean
it
before
I
go
out
tonight.
I
can
do
it
in
the
morning.
A.
daren’t
B.
shouldn’t
C.
needn’t
D.
mustn’t
【答案】C
【解析】
句意：我的房间很乱，但是在今晚我出去之前不需要打扫，我可以明天早晨再打扫。A.不敢；B.不应该；C不需要；D.不许。根据句意，故选C。
3．（2017?江苏）
_______
not
for
the
support
of
the
teachers,
the
student
could
not
overcome
her
difficulty.
A.
It
were
B.
Were
it
C.
It
was
D.
Was
it
【答案】B
【解析】考查虚拟语气和倒装。虚拟语气中，be动词统一用were；虚拟语气的省略形式主要是把if省略，同时把were/should/had提前，即Were
/Should/
Had
I...，故选B。句意：要不是老师们的支持，该生是无法克服她自己的困难的。
4．
(2017·江苏卷)
____________
not
for
the
support
of
the
teachers,
the
student
could
not
overcome
her
difficulty.
A.
It
were
B.
Were
it
C.
It
was
D.
Was
it
【答案】B
【解析】考查虚拟语气的省略。虚拟语气中，be动词统一用were；虚拟语气的省略形式主要是把if省略，同时把were/should/had提前，即Were
/Should/
Had
I...，故选B。
5．（2017?江苏）
_______
not
for
the
support
of
the
teachers,
the
student
could
not
overcome
her
difficulty.
A.
It
were
B.
Were
it
C.
It
was
D.
Was
it
【答案】B
【解析】考查虚拟语气和倒装。虚拟语气中，be动词统一用were；虚拟语气的省略形式主要是把if省略，同时把were/should/had提前，即Were
/Should/
Had
I...，故选B。句意：要不是老师们的支持，该
生是无法克服她自己的困难的。
6．（2017·北京）If
the
new
safety
system
_______
to
use,
the
accident
would
never
have
happened.
A.
had
been
put
B.
were
put
C.
should
be
put
D.
would
be
put
【答案】A
【解析】句意：如果这个新的安全系统被投入使用过的话，这个事故就不会发生了。根据主句确定是对过去情况的虚拟，所以从句谓语用had
done形式，此外根据句意可知是被动，用被动语态，故A项是正确的。
1．(2016·浙江，15)________(have)the
governments
and
scientists
not
worked
together，AIDS?related
deaths
would
not
have
fallen
since
their
highest
in
2005.
【答案】Had　
【解析】句意：如果政府和科学家不共同努力，与艾滋病相关的死亡就不会从2005年的最高点下降。这是一个省略了从属连词if的虚拟语气句，使用了倒装句式。根据主句的would
not
have
fallen可知，这里是表示过去的虚拟语气，所以用had。
2．(2016·浙江，17)George
can't
________(go)too
far.His
coffee
is
still
warm.
【答案】have
gone
【解析】句意：乔治不可能走得太远了。他的咖啡仍然是温的。can't
have
done是对过去的否定推测。
3．(2016·北京，34)Why
didn't
you
tell
me
about
your
trouble
last
week？If
you
________(tell)me，I
could
have
helped.
【答案】had
told　
【解析】句意：上个星期你为什么不告诉我你的麻烦事？如果你告诉我了，我就能帮你。根据句意和相关信息判断，条件句表示与过去事实相反的假设，此时从句用过去完成时，主句谓语用“情态动词＋have
done”形式。