683　too…not to与not/never too…to

① too…not to同too…to意思相反，表示的是肯定意义，主语通常是人，意为“非常……能，很……不会不”。

He is too careful not to have noticed that. 他很细心，不会没注意到那一点。

She is too clever not to understand the question. 她很聪明，必定会理解这个问题。

Tom is too wise not to work out the math problem. 汤姆很聪明，不会解不出那道数学题。（=Tom is so wise that he can work out the math problem.）

You were too angry not to say it. 你在气头上，不免说出这样的话来。

② not/never too…to通常表示肯定意义，意为“不太……而能”，也可表示否定意义，意为“不太……不能”。

She is not too tired to walk on. 她不很累，还能继续走。

He is not too old to work. 他年纪不太大，还能工作。

One is never too old to learn. 人们年纪再大也能学习。/活到老，学到老。

He was not too foolish to answer the question. 他不会笨到连这个问题都答不出。（肯定）

He was not too smart to jump at the opportunity. 他不够机灵，没有抓住这个机会。（否定）

比较

She is too clever not to understand what you mean. 她很聪明，不会不理解你的意思。（肯定）

She is not too clever to understand what you mean. 她不太聪明，理解不了你的意思。