function CheckForm() { 
 var name = volunteer_form.name.value;
 if (name == "") { 
    alert("Please enter your name."); 
    volunteer_form.name.focus();
    return false; 
}
 var email = volunteer_form.email.value;
 if (volunteer_form.email.value == "") {
    alert( "Please enter your email address." );
    volunteer_form.email.focus();
    return false ;
}
 if (volunteer_form.email.value.indexOf ('@',0) == -1 ||volunteer_form.email.value.indexOf ('.',0) == -1){
    alert ("The email address you entered is not valid. Please re-enter your email address.")
    volunteer_form.email.focus();
    valid = false; 
    return false ;
}
 var chkd1 = 0;
 var ChkBxRadio1 = new Array ("gardens","wetlands","educational","special","tram");
 for (var i = 0; i < ChkBxRadio1.length; i++){
 if (document.getElementById(ChkBxRadio1[i]).checked){
  chkd1++;
  }
}
 if (chkd1==0) {
    alert("Please select what you are interested in volunteering for.");
    return false;
}
 var chkd2 = 0;
 var ChkBxRadio2 = new Array ("m-fb5","m-fa5","s-sb5","s-sa5");
 for (var i = 0; i < ChkBxRadio2.length; i++){
 if (document.getElementById(ChkBxRadio2[i]).checked){
  chkd2++;
  }
}
 if (chkd2==0) {
    alert("Please select what times you are available to volunteer.");
    return false;
}
 return true; 
}