Question

What is the difference between over about and for?

Answer 1

over: during/throughout a period of time 

for: unspecific period: he studied for 3 hours ( when began and finished are not known)

about (as far as i know) cann't be copmapred  to both the above; it gives the sense of relativety like almost and nearly..

 

  

 

 

Answer 2

No. Totally Wrong. Read this article about prepositions: http://grammar.ccc.commnet.edu/grammar/prepositions.htm