function validation(){
	var lang = document.getElementById("lang").value;
	if (document.getElementById("name").value == ""){
		if (lang == "c") alert ("請輸入名稱");
		else alert("Please input name");
		document.getElementById("name").focus();
		return false;
	}
	if  (!(document.getElementsByName("title")[0].checked || document.getElementsByName("title")[1].checked)){
		if (lang == "c") alert ("請輸入稱謂");
		else alert("Please input title");
		document.getElementsByName("title")[0].focus();
		return false;
	}
	if (document.getElementById("phone").value == ""){
		if (lang == "c") alert ("請輸入聯絡電話");
		else alert("Please input contact");
		document.getElementById("phone").focus();
		return false;
	}
	if (isNaN(document.getElementById("phone").value) || (document.getElementById("phone").value.length) != 8){
		if (lang == "c") alert ("聯絡電話須為8位數字");
		else alert("Contact number should be of 8 numeric digits.");
		document.getElementById("phone").focus();
		return false;
	}
	if (document.getElementById("loan_amt").value == ""){
		if (lang == "c") alert ("請輸入貸款額");
		else alert("Please input loan");
		document.getElementById("loan_amt").focus();
		return false;
	}
	if (isNaN(document.getElementById("loan_amt").value) || !(parseInt(document.getElementById("loan_amt").value) >= 10000 && parseInt(document.getElementById("loan_amt").value) <= 800000)){
		if (lang == "c") alert ("貸款額須為10,000至800,000之間的數字");
		else alert("Loan amount must be between HK$10,000 and HK$800,000.");
		document.getElementById("loan_amt").focus();
		return false;
	}
	if (document.getElementById("period").value == ""){
		if (lang == "c") alert ("請輸入年期");
		else alert("Please input period");
		document.getElementById("period").focus();
		return false;
	}
}