不定式主表被大全.doc

第一种情况：主---谓---宾
不定式和它前面被修饰的名词或代词构成逻辑上的动宾关系，又和该句主语构成逻辑上的主谓关系时，不定式常用主动形式。
动宾关系
e.g I have a letter to write.

主 谓 关系
Have you anything to be sent?
技巧：1.当不定式的动作是由主语发出的，用主动式 to do.
2. 当不定式的动作由别人发出的，用被动式 to be done
第二种情况：不定式作表语形容词的状语，和句中主语构成逻辑上的动宾关系时，不定式用主动形式。
e.g He is hard to talk to .
The book is difficult to understand.
=The book is difficult for people to understand.
但强调受事者，也可以用不定式的被动式
e.g The handwriting is very difficult to be read.
第三种情况：There be 结构中，当说话人考虑的是必须有人去完成某事时，不定式用主动形式。
e.g 1. There is a lot of work to do .
(sb has to do it )
当说话人强调的是事情本身必须完成时，可以用不定式的被动式。
2.There is a lot of work to be done.
(The work has to be done)
第四种情况：
1. with sb/sth to do, sb do…
2. give sb sth to do .
3. sb do +特殊问词+to do
e.g 1. Mr Li felt like a cat on hot bricks, with so much work to do .
(to do 动作由 主语MrLi 发出)
2.He gave me a book to read.
( to read 动作由 语me 发出)
3.I can’t decide which sweater to
buy. (tobuy动作由I 发出)
第五种情况：
1. be to blame.(被责备)
2. be to let .(出租)
e.g 1. I am to blame.
2. The house is to let.