第1个回答 2019-02-23
动词的语态
语态有两种：主动语态和被动语态。
主语是动作的发出者为主动语态；主语是动作的接受者为被动语态。
1）若宾语补足语是不带to
的不定式，变为被动语态 时，该不定式前要加"to"。此类动词为感官动词。
feel,
hear,
help,
listen
to,
look
at,
make,
observe,
see,
notice,
watch
the
teacher
made
me
go
out
of
the
classroom.
-->
i
was
made
to
go
out
of
the
classroom
(by
the
teacher).
we
saw
him
play
football
on
the
playground.
-->
he
was
seen
to
play
football
on
the
playground.
2）情态动词+
be
+过去分词，构成被动语态。
coal
can
be
used
to
produce
electricity
for
agriculture
and
industry.
第2个回答 2020-05-07
5）短语动词是不可分割的整体，改为被动语态时要保持其完整性，介词或副词不可遗漏。如：
We
must
take
good
care
of
the
young
trees．→The
young
trees
must
be
taken
good
care
of．
6）含有宾语从句的主动结构变为被动结构时，通常用it作为被动结构的先行主语，从句放在句子后面；也可采用另一种形式。可以这样转换为被动结构的动词有know，say，believe，find，think，report等。如：
People
believe
that
he
is
ill．→It
is
believed
that
he
is
ill．（或：He
is
believed
to
be
ill．）
3．被动语态改为主动语态的方法：
被动语态中介词by后的宾语改为主动语态中的主语（或按题意要求确定主语），按照这个主语的人称和数以及原来的时态把谓语动词形式由被动语态改为主动语态。注意在主动语态中有的动词要求不带to的动词不定式作宾语补足语，此时要把被动语态中的to去掉。被动语态的主语用来作主动语态的宾语。如：
History
is
made
by
the
people．?The
people
make
history．
4．不能用于被动语态的情况
1）某些表示“静态”的及物动词（表示状态而不是动作，而且常常是不可用于进行时态的动词）如have，fit，suit，hold（容纳），cost，
suffer，last（持续）等不能用于被动语态。如：
They
have
a
nice
car．他们有一辆漂亮的汽车。
My
shoes
don't
fit
me．我的鞋不合适。
My
brain
can't
hold
so
much
information
at
one
time．我的脑子一下子记不住这么多资料。
How
much
／What
does
it
cost？这值多少钱？
Our
holiday
lasts
10days．我们的假期有十天。
This
food
will
last（them）（for）3days．这食物足够（他们）（吃）三天。
2）不是所有带介词的动词都能用于被动结构。若是构成成语动词通常有被动态，若不构成成语动词则无被动态。试比较：
They
arrived
at
a
decision．?A
decision
was
arrived
at．他们作出了决定。
They
arrived
at
the
station．他们到达车站。（不说：The
station
was
arrived
at．）
He
looked
into
the
question．?The
question
was
looked
into．他调查了这个问题。
3）动词leave（离开），enter（进入），join（参加）不可用于被动语态。如：
The
car
left
the
road
and
hit
a
tree．车子离开了道路，撞上了树。
4）某些及物动词可作不及物动词用，特别是后加副词（如well，
easily等）时。主动语态有被动含义，这类动词常见的有sell，write，
wear，wash，cook，open，close，lock，read，record等。如：
His
new
novel
is
selling
well．他的新小说很畅销。The
cloth
washes
well．这布很耐洗。
This
material
won't
wear．这种材料不耐穿。His
play
won't
act．他的戏剧不会上演。
The
window
won't
shut．这窗关不上。The
door
won't
open．这门打不开。
The
door
won't
lock．这门锁不上。This
poem
reads
well．这首诗读来很好。