不能去掉,这是动词不定式作定语,也叫做反射不定式,如果反射不定式里的动词为不及物动词,或者需要搭配一定介系词才能使用,这个介系词是不能漏掉的。 动词不定式用作定语,通常皆置于其所修饰的名词或代词之后。它与其所修饰的名词或代词可能是主谓关系。如: The next train to arrive was from New York. 下一列到站的火车是从纽约开来的。 All dead. I was the only one to grow up. 都死了。我是惟一成活的。 He was always the first to come and last to leave the office. 他总是第一个到办公室,最后一个离开。(first与last之后省去person了) 也可能是动宾关系,这时不定式即通常所谓的反射不定式。如: It was a game to remember. 那是一场令人难忘的球赛。 He has too many things to do. 他要做的事太多了。 I have nothing to say on this question. 在这个问题上,我没有什么话要说。 反射不定式也可以是“不定式+介词”结构,这里的介词一般不可省去。如: I need a pen to write with. 我需要一支笔写字。 Give me some paper to write on. 给我一些纸写字。 There are some things to be grateful for. 有一些事应该为之表示感激。 此外还有两种抽象名词常后接不定式,一种是与常后接不定式的动词同源的名词。如: His wish to visit China is quite understandable. 他访问中国的愿望是完全可以理解的。(名词wish与常后接不定式的动词wish同源) Her decision to be a pianist is final. 她对要做一个钢琴家已下了最后的决心。(decision与常后接不定式的动词decide同源) 另一种是与常后接不定式的形容词同源的名词。如: He is reputed for his ability to speak four languages. 他以能讲4国语言而闻名。(ability与常后接不定式的形容词able同源) The child was all eagerness to go on the picnic. 这孩子对去野餐非常心切。(eagerness与常后接不定式的形容词eager同源)
不可以,这里的knife做的事介词with的宾语,cut it with the knife; 类似的还有I have a book to read, (动词宾语) :Read a book I have a baby to look after(不及物动词+介词宾语) :look after a baby I have a pen to write letters with.(介词宾语) :write letters with a pen