一、too... to... 的意义

　　too... to 句型形式上是肯定的，但是它在意义上却是否定的，表示"太……而不能……"。too 的后面接形容词或副词的原级，to 的后面接动词原形。too... to...句型是简单句。例如：

　　He is too young to join the army. 他年龄太小，不能参军。

　　二、动词不定式的逻辑主语

　　动词不定式所表示的动作的执行者与整个句子的主语不指同一人或物时，需要在动词不定式前加上一个逻辑主语(常用for sb.)。例如：

　　The maths problem is too difficult for me to work out. 这道数学题太难我解不出来。

　　三、too... to... 结构表达肯定的意义

　　1. too 前面含有表示否定意义的词，如: not, never, nothing等时，too... to... 结构不表示否定的意义。例如：

　　It is never too old to learn. 活到老，学到老。(要学永远都不迟。)

　　2. 如果在too... to...这种结构的前面出现了only, 不仅免去了too的否定意义，反而加强了too的肯定语气，only too 相当于very 或very much。例如：

　　I shall be only too pleased to get home. 到了家我将极其高兴。

　　3. too后接表示感情的形容词，如glad, pleased, happy, sad等时，too... to...句型不再表示否定意义，而表示的是肯定意义。例如：

　　He is too sad to hear the bad news. 听到这个不幸的消息他太悲伤了。

　　四、too... to... 结构与enough...to... 结构及so... that...结构的相互转换

　　1. 将too...to...结构转换为enough... to... 结构时，要注意：

　　(1) enough 前的形容词或副词应是too前面形容词或副词的反义词；

　　(2) enough... to... 句式须用否定式；

　　(3) too... to...结构有逻辑主语时，

　　enough... to... 结构也要加上逻辑主语。例如：

　　She is too young to do the work. = She isn't old enough to do the work.

　　The problem is too hard for him to work out.= The problem isn't easy

　　enough for him to work out.

　　2. 将too...to...结构转换为so... that... 结构时，要注意：

　　(1) so... that... 结构是复合句，so 的后面接形容词或副词的原级，that的后面接从句。

　　(2) that后面的从句要用否定形式。例如：

　　She is too young to go to school. = She is so young that she can't go to school.

　　请同学们做做下列中考题，以便检验你对too... to...用法的掌握情况。

　　变换下列句型：

　　1. a. The box is so heavy that I can't carry it.

　　b. The box is ________ heavy______ ________ ________ carry.

　　c. The box is not ________ ________ for me to carry. (江苏省盐城市)

　　2. a. The maths problem isn't easy enough for me to work out.

　　b. The maths problem is ________ difficult ________ I can't work it out.

　　c. The maths problem is ________ difficult ________ ________ ________ work out. (江苏省扬州市)

　　3. a. The book is interesting enough for　everybody to read.

　　b. The book is ________ interesting________ everybody likes to read　it. (江苏省苏州市)

　　Keys: 1. b. too, for me to c. light enough

　　2. b. so, that c. too, for me to

　　3. b. so, that

　　(文/张 贺　邹秀萍；　英语辅导报初三版03--04学年度第42期；版权归英语辅导报社所有，独家网络合作伙伴新浪教育，未经许可，不得以任何形式进行转载。)