1. be afraid of是固定词组，意思为“担心，害怕”。afraid 之后可跟of +动名词、动词不定式、从句结构。指“害怕人或物，怕做某事”时用of+动名词、名词、代词结构；如果后面跟不定式则侧重表示“因担心后面严重而不敢也不愿意做某事”。
1）be afraid+ to-infin.害怕：She is afraid to go through the wood but she has to. 她虽然害怕，可还是不得不穿过这树林。
2）be afraid of+动词ing形式：I am afraid of going through that wood, I'll take the road.我害怕穿过那座树林，我将走大路。

3）be afraid+that从句，意思是“恐怕”：I am afraid(that)it is true.恐怕这是真的。
2.be afraid that+将来时态，表示“恐怕”：I am afraid (that) the train will be late. 我恐怕火车会晚点。
3.be afraid of sb. or sth.害怕。：She is afraid of you 她害怕你。Are you afraid of death?你害怕死吗?
考点：
4.be afraid +not 或者 so： You come to our party? --l am afraid not.你来参加我们的聚会吗?恐怕不啦! (是一种婉转的口吻)。Will the train be late? --I am afraid so. 火车会晚点吗?我想是的。句中的not或者so代表的是从句部分。这种形式常出现在完形填空中。
