The Preposition

For: "For" has a great many meanings:

1. Space of time or distance: I' am staying here for a week.

2. Purpose, aim, intention: We come here for Arabic lessons.

3. Amount: The house was sold for 6.000.
 

4. Direction: Which is the train for Syria.

5. Point of time: The meeting is arranged for five o'clock.

6. Cause: I couldn't see anything for smoke.

7. Exchange: I'll give you my watch for your camera.

8. Advantage (or disadvantage):

This holiday has been good for you, too much work is bad for you.  

From:

The principal meanings of from are:

1. A motion away, departure, removal: He rose from  his chair.

2. A starting point, place of origin: He read from page 15 to page 23.

3. Cause: She is suffering from a bad headache.

4. Separation: He is far away from home and wife and children.