资源简介

(共13张PPT)
情态动词（二）
一、表推测的情态动词
表推测时，英语中只使用must,
may,
might,
may
not和can't；
这五个表达的语气依次递减：must一定（语气肯定）;
may也许（不是很肯定）;
might或许（比may语气更弱）;
may
not也许不（表否定）;
can't一定不（must的反义）
⑶
疑问句中一般can和could提问
e.g:
It’s
so
late.
Who
can/could
it
be?
Can
he
be
at
home
now?
注:
might,
could并非may,
can的过去式,而表示语气较为委婉或可能性较小。
e.g:
It
can’t/couldn’t
be
the
headmaster.
He
has
gone
to
America.
He
may
not/might
not
know
the
scientist.
⑵
否定句中用can’t
/
couldn’t(一定不),
may
not/might
not(可能不)。
e.g:
He
must/may/might/could
be
our
teacher.
He
may/might
know
the
answer
to
this
question.
⑴
在肯定句中一般用must一定,
may也许,
might
/
could或许
（一）情态动词表推测的三种句式
⑶
对过去情况的推测，用“情态动词
+
have
+过去分词”或“情态动词+have
been
doing
”
e.g:
It
must/may/might/have
rained
last
night
.
The
ground
is
wet.
Can
/
Could
he
have
gotten
the
book？
He
can't(couldn't)
have
left.
I
saw
him
a
minute
ago.　
He
must
/
may
/
might
/
have
been
waiting
for
a
long
time.
⑵
对现在此时此刻情景的推测，用“情态动词
+be
doing”
e.g：He
must
/
may
/
might
/
could
be
listening
to
the
radio
now.
She
can’t(couldn’t)
be
working
now.
e.g：She
must/may/might/could
be
in
the
office.
She
must
/
may
/
might
/
could
arrive
before
5
o'clock.
He
can't(couldn't)/may(might)
not
be
at
home
at
this
time.
⑴
对现在或将来情况的推测，用“情态动词
+
be或动词原形”。
㈡
情态动词表推测的三种时态
1.
It
can't
be
Tom
who
stole
the
money.
2.
Mr.
Smith
can't
have
gone
to
Beijing,
for
I
saw
him
in
the
library
just
now.
3.
He
must
know
the
answer
to
this
question.
4.
It
is
cold
in
the
room.
They
must
have
turned
off
the
heating.
5.
There
is
no
light
in
the
room.
Can
they
have
gone
out?
6.
He
may
not/might
not
know
the
girl.
7.
He
could
be
listening
to
the
radio
now
8.
He
must
have
been
waiting
for
a
long
time.
9.
Can
he
be
at
home？
10.
The?door?was?locked.?He
might?not?have?been?at?home.
11.
He?didn't?hear?the?phone.
He?might?have?been?asleep.?
试一试：翻译下列句子，并总结是哪种用法
二、表虚拟的情态动词
“情态动词+have
done”表示虚拟，主要有should/ought
to
have
done(本该做却没做）；shouldn't/ought
not
to
have
done
(本不应该做却做了);
could/might
have
done(本能够做却没做）；would
have
done(本会做却没做)
;
need
have
done
(表示本需要做却没做);
needn't
have
done(表示本没必要做却做了);
would
rather
have
done(宁愿做了却没做)
⑴
“should
+
have
done”
/
“ought
to
+
have
done”表示过去应该做而没做,
含有责备或
遗憾的语气
e.g:
I
should
have
told
you
about
it
earlier.
Look,
Tom
is
crying.
I
shouldn’t
have
been
so
hard
on
him.
You
ought
to
have
gone
home
last
Sunday.
⑵
“could
+
have
done”表示过去本来能够做某事而没有做。
e.g:
He
could
have
passed
the
exam,
but
he
was
too
careless.
⑶
“might
+
have
done”表示过去本来可以做某事而没有做
e.g:
She
might
have
achieved
greater
progress,
if
you
had
given
her
more
chances.
⑷
“would
+
have
done”，表示对过去事情的假设，意思是“本来会做”。
e.g:
I
would
have
told
you
all
about
the
boy’s
story,
but
you
didn’t
ask
me.
Without
your
help,
I
wouldn’t
have
achieved
so
much.
⑸
“need
+
have
done”表示本来需要做某事而没有做，needn’t
have
done为本不必做某事而实际
上做了。
e.g:
I
needn’t
have
bought
so
much
wine—only
five
people
came.
He
need
have
hurried
to
the
station.
In
that
case,
he
wouldn’t
have
missed
the
train.
⑹
“
would
rather+
have
done”
表示宁愿过去干了某事，而实际上并没发生；其否定形式意思为表示宁愿过去没干某事，而实际上却做了。
e.g:
I
raised
objections
at
the
meeting.
I’d
rather
haven’t.
⑺
其它结构中的虚拟语气现象
1)
would
like
to
have
done
想要做却没做
e.g:
I
would
like
to
have
attended
your
party,
but
I
was
too
busy.
2）was/
were
to
have
done打算做却没做
e.g:
The
plane
was
to
have
taken
off
at
8
o’clock,
but
it
was
held
up
because
of
a
heavy
fog.
3）was/
were
supposed
to
have
done
相当于should
have
done
e.g:
You
are
supposed
to
have
completed
the
work
by
now.
1.
You
shouldn't
tell
him
about
it.
2.
You
shouldn't
have
told
him
about
it.
He
is
so
sad
now.
3.
You
needn't
do
it.
4.
You
needn't
have
watered
the
flowers.
Look,
it's
raining.
5.
I
am
afraid
I
couldn't
come
tonight.
6.
I
could
have
come
yesterday,
but
my
mother
was
seriously
ill.
7.
He
might
not
know
the
truth.
8.
It's
no
use
going
to
his
house.
He
may
have
gone
somewhere
else.?
9.
I
would
rather
stay
at
home.
10.I
would
rather
have
refused
his
offer.
对比下列句子：
结论：should
do
should
have
done
needn’t
do
needn’t
have
done
................
................................
时间：____________
___________________
动作：____________
____________________
写出下列表推测的情态动词和表虚拟的情态动词的含义
A:
表推测的情态动词
must
have
done
:
might/may
have
done:
couldn't(can't)
have
done:
should
have
done/ought
to
have
done:
shouldn’t
have
done/ought
not
to
have
done:
need
have
done:
needn’t
have
done:
could
have
done:
might
have
done:
would
have
done:
B:
表虚拟的情态动词
He
might
have
left
yesterday,
nobody
saw
him
this
morning.
He
might
have
left
yesterday,
but
his
mother
was
ill.
比较:
谢谢观赏

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