If you have just found some penpals among men and don't know how to correspond with them please remember that you should answer everybody if it is the first letter. You should prove them that you do exist. If you don't like a man, write him a letter with a polite refusal but don't hurry. You can't understand whether you like a man or not from his first letter. Some men can't write good letters though they are very good persons. Don't hesitate to ask them questions yourself.
There are a lot of cases when women returned to rejected letters, developed relationships with these penpals and became a couple in future. Therefore it is important to refuse men softly in order to remain fiends. So, in future if you decide that you have made a mistake and want to continue correspondence with that men you will be able to do it. By the first meeting with your penpals you should know practically all about each other. Disappointments can come out in personal meeting because of lack of information about each other.
So, the main rules for first letters with your male penpals are the following: don't hurry up with the refusal, ask questions yourself and try to learn more information about men before meeting with them.