情态动词的用法
一?/p>
can
?/p>
could
情态动?/p>
用法
例子
补充说明
can/could
表示能力
1
?/p>
I can speak fluent English now,
but I couldn’t last year.
Can
表现在能力;
Could
表示?
去能?/p>
.
可用
be
able
to
?
替;
was/were able to
表示?
功做了某?/p>
在肯定句?/p>
?/p>
表示客观
可能性,
并不涉及具体?/p>
事会发生?/p>
常用来说明人
或事物的特征?/p>
要表达具
体某事实际发生的可能
性时,不?/p>
can
,需?/p>
could
?/p>
may
?/p>
might
?/p>
1.
I
may
stay
at
home
this
weekend.
(实际可能性)
2.
Peter might come to join us.
(
?/p>
际可能?/p>
)
3.
It
will
be
sunny
in
the
daytime
,but
it
could
rain
tonight.
(
实际可能?/p>
)
1.
can
用于否定和疑问句
(could
不限
)
2.
can (be)
表示有时候会(常?/p>
sometimes, at times
连用?/p>
表示请求和允许?/p>
表示?/p>
求,
口语中常?/p>
could
?/p>
?/p>
can
,使语气更委婉?/p>
1
?/p>
Can we turn the air conditioner
on?
.
2.
I wonder if I could just ask you
to sign this.
1.
请求?/p>
could
语气委婉
2.
允许不用
could.
表示对现在的动作或状
态进行主观的猜测?/p>
主要
用在否定句和疑问句中?/p>
1
?/p>
It
can’t
be
easy
caring
for
a
man
and
a
child
who
are
not
your own.
2
?/p>
Can the man over there be our
head master?
表示惊异?/p>
怀疑?/p>
不相?/p>
等态度,主要用在否?/p>
句、疑问句和感叹句中?/p>
1
?/p>
Can
this
be
an
excuse
for
not
giving them help?
2
?/p>
This can’t be true.
3
?/p>
How can you be so crazy!
特别提示?/p>
?/p>
1
?/p>
could
用来表示请求时,语气委婉,主要用于疑问句,不能用于肯定句,回答应该用
can
(即?/p>
could
不能用于
现在时态的简略答语中?/p>
。如?/p>
—?/p>
Could I use your dictionary?
—?/p>
Yes, you can.(
否定回答可用?/p>
No, I
?/p>
m afraid not.)
(2)
can
?/p>
be able to
区分
can(could)
?/p>
be able to
都可以表示能力,意思上没有区别。但
can
只有现在式和过去式,?/p>
be able to
则有更多
的形式。如?/p>
I
?/p>
ve always wanted to able to speak fluent English.
Those bags look really heavy, are you sure you
?/p>
ll be able to carry them on your own?
但是,表示在过去某时的某一场合经过一番努力,终于做成了某事,通常不用
could
,而用
was/were
able
to
?