2. 有些形容词可用不定式短语作状语．
　　　a. 表示某种感情的原因状语，这类形容词主要有：amazed, angry, annoyed, ashamed, bored, delighted, glad, disappointed, embarrassed, excited, happy, pleased, proud, sorry, shocked等，如：
　　　　I am very glad to meet you.

　　　b. 用在以下结构中表示结果状语：
　　　　too … to （太…不能）
　　　　not /never too … to （不太…能）
　　　　but/only too … to （非常）
　　　　enough … to （足够…能）
　　　　not … enough to （不够…不能）
　　　　so … as to （如此…以至于）
　　　　He is too young to understand such things.
　　　　One is never too old to learn.
　　　　We are only (but) too glad to help you.
　　　　I was foolish enough to accept his offer.
　　　　He is not tall enough to reach the top of the shelf.
　　　　She was so angry as to be unable to speak.