第1个回答 2022-07-17
动词不定式主动表被动：
(1) 主语+及物动词+宾语+ to do(作定语).这时,不定式虽与被修饰词（宾语）之间是动宾关系,但与句子的主语有主谓关系.另外,不定式若是不及物动词时,应加上结构上或意义上所需要的介词.例如：
I have a meeting to attend today.
Do you have anything to say?
Would you like something to drink?
She had to find a room to live in.
I have borrowed a novel to read during the vacation.
I have several models for you to choose from.
但是如果不定式和主语之间没有这种主谓关系,则需要用不定式的被动形式.例如：
I'm going to Beijing next week.Do you have anything to be taken to your parents?
I’ll go to the post office.Do you have a letter to be posted?
以上两句用不定式的被动形式作定语,表明you不是take/post动作的执行者.
(2) 主语+及物动词+间接宾语+直接宾语+ to do(作定语).这时,不定式与被修饰词(直接宾语)之间是动宾关系,而与间接宾语之间有主谓关系.另外,不定式若为不及物动词时,应加上结构上或意义上所需要的介词.例如：
He lent me some books to read.
Give me a pen to write with.
He lent me a piece of paper to write on.
(3) This/That) +be +名词+ to do(作定语).例如：
This is an easy question to answer.
That is a good place to live in.
(4) there be+名词+to do(作定语).
此结构中,用来修饰主语的不定式可以用被动形式,也可以用主动形式,在口语中用主动形式的时候更多一些.例如：
There is nothing to worry about.
There is no time to lose (to be lost).
There are still many difficulties to overcome (to be overcome).
但有时候用主动和被动可分别表示不同的意思：不定式用主动式作定语,重点在人,用被动形式作定语,重点在物.试比较:
There is nothing to do now.(We have nothing to do.)
There is nothing to be done now.(We can do nothing now.)
There is nothing to see.(nothing that is worth seeing)
There is nothing to be seen.(nothing there at all)
(5) 主语(人或物) + be + 形容词+ to do (作状语).
常见的形容词有：easy,hard,difficult,dangerous,nice,good,interesting,important,fit,impossible,pleasant,light,heavy,bitter,comfortable,cheap,expensive,funny,exciting,delicious等.若不定式动词是不及物时应加上结构上或意义上所需要的介词.例如：
The water in the lake is unfit to drink.
The strawberries are nice to eat.
The problem is easy to work out.
The man is hard to please.
The room is expensive to live in .
(6) 主语+及物动词+形容词+to do(作宾补).这时,不定式与宾语之间有动宾关系,而与句子的主语有主谓关系.另外,不定式为不及物动词时,应加上结构上或意义上所需要的介词.例如：
I find the lecture difficult to understand.
I find him pleasant to work with.
(7) “too+形容词+to do(作状语)”结构中.例如：
This book is too difficult to understand completely.
The passage is too hard to translate.
(8) “疑问代词 + 不定式”结构中.例如：
I don't know what to do next.
She will tell you which bus to take.
Do you know whom to go with?
The mother didn’t know who to blame for the broken glass.
(9) “be+ to do(作表语) 结构中.例如：
The house is to let.
I feel it is your husband who is to blame for the spoiled child.(02上海)
The reason is not far to seek.