在近几年的中考中,我们不难发现enough to与so...that,too...to结构句型的转换不时出现在各地的中考试题中,然而从学生的答题中却发现,多数学生对此掌握得不好,答题屡屡出错。其实enough to与so...that ,too...to 是现用人教版新目标初中英语教材中的三个重要结构。它们在一定的条件下,可以相互转换,现就此作一归纳。
　　
　　一、too ...to与so ...that结构的转换
　　
　　too ...to 句型常用来表示“太……以致不能”的意思。so ...that 句型常用来表示“如此……以致”的意思。too ...to 结构是一个简单句, so... that结构常是复合句。当that引导的从句为否定形式,且主句中的主语与从句的主语相一致时,so...that 结构可转换为too...to结构。例如:
　　Tom is so young that he can’t join the army.
　　→Tom is too young to join the army.
　　I’m so tired that I can’t walk on.
　　→I’m too tired to walk on.
　　当that 引导的从句为否定式,但从句主语与主句主语不相同时,so ...that 可转换为too... for sb to 结构。例如:
　　The box is so heavy that I can’t lift it.
　　→The box is too heavy for me to lift.
　　The question is so difficult that he can’t answer it.
　　→The question is too difficult for him to answer it.
　　
　　二、so... that 与enough to 结构的转换
　　
　　当that引导的从句为肯定式,且从句主语与主句主语相同时,so...that句型可转换为enough to句型结构。例如:
　　Mike is so old that he can go to school.
　　→Mike is old enough to go to school.
　　The boy is so strong that he can lift the heavy box.
　　→The boy is strong enough to lift the heavy box.
　　当that引导的从句为肯定式,但从句主语与主句主语不相同时,so ...that可转换为enough for sb to 结构。例如:
　　The box is so light that the child can lift it.
　　→The box is light enough for the child to lift.
　　They walked so slowly that we could keep up with them.
　　→They walked slowly enough for us to keep up with them.
　　
　　三、enough to与too...to结构的转换
　　
　　enough to 所在句子为不定式时,enough to 结构可转换为too ...to 结构,但转换后too... to 结构中的形容词、副词要用其相应的反义词。例如:
　　He isn’t old enough to do the work.
　　→He is too young to do the work.
　　Tom didn’t walk slowly enough for us to keep up with him.
　　→Tom walked too fast for us to keep up with him.
　　 以上是enough to,so... that,too... to结构句型间的常见转换,也是当前各类考试中的常见题型,还需要我们不断学习和总结。
　　(责任编辑 周侯辰)