要分为介词to 和不定式符号to
1.介词to 有look farword to ,devote to ,get down to ,the key to ,make contributions to ,contribute to
2.动词不定式符号to 有offer to do,decide to do,hope to do,manage to do,stop to do,need to do,would like to do,want to do,prefer to do,plan to do,intend to do,refuse to do,try to do,remember to do,forget to do,差不多了.