Special difficulties

形容词 + 动词不定式

e.g. He was delighted to learn that his offer has been accepted.

e.g. I was glad to hear that he had arrived.

e.g. He was anxious to leave early.

（1）感情形容词后的不定式通常是表示原因，在句中做原因状语

happy, relieved, astonished, amazed, surprised, horrified, disappointed, sad, embarrassed, shocked

e.g. He was frightened when he saw the snake.→He was frightened to see the snake.

e.g. I was sorry when I learnt that he had an accident. →I was sorry to learnt that he had an accident.

 (2) 不定式也可以放在表语之后，主语是不定式的实际宾语

e.g. The car is hard to park.

e.g. Some questions are awkward to answer.

 (3) 在少数几个动词(learn, find, see, hear, be told)后，可用作结果不定式

e.g. He lived to see his inventions come to success.

e.g. He woke up to find everyone gone.

(4) 在不定式前加only，表示意想不到的，出乎意料的结果.

Eg: He hurried to the post office only to find it was shut. 他赶到邮局却发现邮局关门了。