function showhide(which){

if(which=='male'){
document.getElementById("female_form").style.display = "";
document.getElementById("male_form").style.display = "block";
}

if(which=='female'){
document.getElementById("male_form").style.display = "";
document.getElementById("female_form").style.display = "block";
}

if(which=='both'){
document.getElementById("male_form").style.display = "";
document.getElementById("female_form").style.display = "";
}

}