function checkForm(form) {

	if (form.YourName.value == "")  {
		alert ("Please enter your name!")
		form.YourName.focus()
		form.YourName.select()
		return(false); }
	
	if (form.YourEmail.value == "" ||  isEmail(form.YourEmail.value)==false)  {
		alert ("Not a valid e-mail address!")
		form.YourEmail1.focus()
		form.YourEmail1.select()
		return(false);}		
		
	if (form.FriendName1.value == "")  {
		alert ("Please enter your friend's name!")
		form.FriendName1.focus()
		form.FriendName1.select()
		return(false); }		
		
	if (form.FriendEmail1.value == "" ||  isEmail(form.FriendEmail1.value)==false)  {
		alert ("Not a valid e-mail address!")
		form.FriendEmail1.focus()
		form.FriendEmail1.select()
		return(false);}				
			
	// More friend's email 
	if (form.morefriends.value == "1")  {
		
		//email 2
		// Invalid email or name but not email
		if ((form.FriendEmail2.value != "" &&  isEmail(form.FriendEmail2.value)==false) || (form.FriendEmail2.value == "" && form.FriendName2.value != ""))  {
			alert ("Not a valid e-mail address!")
			form.FriendEmail2.focus()
			form.FriendEmail2.select()
			return(false);}
			
		//email but not name
		if (form.FriendEmail2.value != "" && form.FriendName2.value == "")  {
			alert ("Please enter your friend's name!")
			form.FriendName2.focus()
			form.FriendName2.select()
			return(false);}
		
		//email 3
		// Invalid email or name but not email	
		if ((form.FriendEmail3.value != "" &&  isEmail(form.FriendEmail3.value)==false) || (form.FriendEmail3.value == "" && form.FriendName3.value != ""))  {
			alert ("Not a valid e-mail address!")
			form.FriendEmail3.focus()
			form.FriendEmail3.select()
			return(false);}
			
		//email but not name
		if (form.FriendEmail3.value != "" && form.FriendName3.value == "")  {
			alert ("Please enter your friend's name!")
			form.FriendName3.focus()
			form.FriendName3.select()
			return(false);}
			
		//email 4
		// Invalid email or name but not email	
		if ((form.FriendEmail4.value != "" &&  isEmail(form.FriendEmail4.value)==false) || (form.FriendEmail4.value == "" && form.FriendName4.value != ""))  {
			alert ("Not a valid e-mail address!")
			form.FriendEmail4.focus()
			form.FriendEmail4.select()
			return(false);}
			
		//email but not name
		if (form.FriendEmail4.value != "" && form.FriendName4.value == "")  {
			alert ("Please enter your friend's name!")
			form.FriendName4.focus()
			form.FriendName4.select()
			return(false);}	
			
		//email 5
		// Invalid email or name but not email	
		if ((form.FriendEmail5.value != "" &&  isEmail(form.FriendEmail5.value)==false) || (form.FriendEmail5.value == "" && form.FriendName5.value != ""))  {
			alert ("Not a valid e-mail address!")
			form.FriendEmail5.focus()
			form.FriendEmail5.select()
			return(false);}
			
		//email but not name
		if (form.FriendEmail5.value != "" && form.FriendName5.value == "")  {
			alert ("Please enter your friend's name!")
			form.FriendName5.focus()
			form.FriendName5.select()
			return(false);}								
		
	}		

	else return(true);
}