logic: converse propositions

ok, so in the converse of a proposition the subject and predicate are essentially reversed. a very simple example would be. dogs are cats. the converse of that would be that cats are dogs. or so i think ...

in conditional form, something like this ... comes to mind:

if it is raining, i am wet. the converse of that would be: if i am wet, it is raining.

here's one from the text:

some european cars are overpriced and underpowered vehicles.

the converse of that should be:

some overpriced and underpowered vehicles are european cars.

in this case, what i also notice is that the quality and quantity have remained constant.

conversion is an inference that proceeds by interchanging the subject and the predicate terms of a categorical proposition. not all conversions are valid.

conversion is perfectly valid for all E propositions and all I propositions.


Answers ... didn't want to write in the book:

1. E proposition -- no reckless drivers ... are people who are considerate of others... (Equivalent)
   
2. A proposition all commissioned officers in the navy are graduates of west point (Nonequivalent)
3. O proposition some overprices and underpowered vehicles are european cars (equivalent)
4. E proposition no warm blooded animals are reptiles (Equivalent)
   
5. I proposition some elderly persons ... are professional wrestlers ... (Equivalent)