to做介词的时候就接名词，动名词，或者名词性结构，构成不定式时，就接原形。
例句
She went to her room to unpack.
她回到自己的卧室打开行李取出衣物。
Rice aspired to go to college.
赖斯渴望上大学。
I wish to speak to the manager.
我想跟经理说话。
It pleased him to talk to her.
和她谈话让他高兴。
I had to go to the hospital.
我得去医院看病。
He loved her to sing to him.
他喜欢让她唱歌给他听。
