of
1. 表示所属关系：...... 的，属于......
He is a friend of my father's.
他是我办的一个朋友。
One of the longest rivers in the world is the Yangtze River.
世界上最长的河流之一是长江。
I have finished reading the works of Luxun.
我已经读完了鲁迅的著作。
2. 表示具有某种性质的：
This photo is of great value.
这个照片很珍贵。
3. 表示同位关系
At the age of 15, he went England with his parents.
十五岁时，他随父母去了英格兰。
4. 来自......的；出自......
He is a child of the poor.
他是穷人家的孩子。
5. 表示原因，常见于 die of
The little child died of pneumonia.
那个小孩死于肺炎。
6. 有关......的，在......方面
His uncle is hard of hearing.
他的叔叔有点聋。
7. of 后面的宾语正好是前面表语的逻辑主语，如：
It’s very kind of you to do so.
你这么做真是太好了。
for
1. 为了......
Dad bought a flute for me.
爸爸为我买了个笛子。
Here is the present for you.
这是给你的礼物。
2. 作为......
This house was built for a reading room.
这座房子为当作阅览室而修建的。
3. 表原因：由于........
He was blamed for being late again.
他因为有一次迟到而被批评。
4. 表示在时间、距离、范围上“大到......”
The couples have lived here for years.
这对夫妇在这里住了多年。
You can see for miles from top of the hill.
你在小山顶上能看到数英里之外。
5. 就......而言，对......来说
You are too young for the job.
你还太年轻，无法胜任这个工作。
6. 支持......
Are you for or against the desicion?
你是支持还是反对这项决定？
7.往......，朝着......
The team is leaving for Shanghai tomorrow.
这个球队明天动身去上海。
8. for 可以作连词用，引导原因状语从句
They had to take a taxi for there were no buses.
他们只有打车，因为没有公交了。
9. for 引出动词不定式的逻辑主语，表示“对于…而言”，如：
It's easy for me to put him in trouble.
给他找些麻烦对我来说不难。
。