Assuming you're alluding to a straight relationship, the roles of a man are very varied nowadays, certainly a lot more than they used to be. Back in the day the woman would be the family maker and did all the house work and cooking, cleaning etc. The man would have a job to make money and support the family.
However now it's a lot harder to presume someone's role in a relationship based on their gender, you have 'stay at home dads' who look after the kids whilst the woman is off to work, you've got families that work from home that look after the kids, men and women working together in the work place. All of which most would agree is a fantastic step in the right direction.
You can't really label what a man does in a relationship in the same way you can't really label what a woman does because the idea of gender roles has almost completely been abolished.
The main purpose of religion is to provide man with hope!
The cattle
The defense of his country.
to have a lawful and blessed relationship between a man and a woman
This is a relationship term. "His main" is like the man's "wifey" or his main girl. She is the one that he cares for. She is the main girl in his life. Or if he is in an open relationship or he is just simply a player and he talks to many girls there may be one special girl who he always goes back to in the end, which usually means she is "his main"
the main purpose of the crusades was to be themselves
the main purpose of the crusades was to be themselves
The main idea of "The Killers" is innocence. Nick, the main character experiences a loss of innocence throughout the story.
The purpose of Co-Dependents Anonymous is to help men and women to develop healthy relationships. As long as the man and women want a healthy and loving relationship they are qualified for this.
The main purpose is to distribute news to people.
the main purpose of the guitar is to play music
Is the main purpose of using Automata?