ช่วยดูให้หน่อยครับทำไมบันทึกไม่ได้ครับ ผมบันทึกพร้อมกัน 3 ตาราง

	$strMode = $_POST["tMode"];								
$objConnect = mysql_connect("localhost","root","123") or die("Error Connect to Database");				
	$objDB = mysql_select_db("db_transfer");	
	if($strMode == "ADD"){	
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	  $strSQL = "INSERT INTO tbl_student ";
	  $strSQL .="(std_id,id_add,name,class,branch,school,add_date) ";
	  $strSQL .="VALUES ";
$strSQL .="('".$_POST["tstd_id"]."','".$_POST["tid_add"]."','".$_POST["tname"]."','".$_POST["tclass"]."' ";
	  $strSQL .=",'".$_POST["tbranch"]."','".$_POST["tschool"]."','".$_POST["tdate_time"]."') ";
	  $objQuery = mysql_query($strSQL)or die ("Error Query [".$strSQL."]");	
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	  $strSQL1 = "INSERT INTO tbl_vocational ";
	  $strSQL1 .="(std_id,sub_vid,sub_name,cradit,Grade_vocational) ";
	  $strSQL1 .="VALUES ";
$strSQL1 .="('".$_POST["tstd_id"]."','".$_POST["tsub_vid"]."','".$_POST["tsub_name_v"]."'";
	  $strSQL1 .=",'".$_POST["tcradit_v"]."','".$_POST["tGrade_vocational"]."') ";
	  $objQuery = mysql_query($strSQL1)or die ("Error Query [".$strSQL1."]");			
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	  $strSQL2 = "INSERT INTO tbl_bachelor ";
	  $strSQL2 .="(std_id,sub_bid,sub_name,cradit,Grade_bachelor) ";
	  $strSQL2 .="VALUES ";
 $strSQL2 .="('".$_POST["tstd_id"]."','".$_POST["tsub_bid"]."','".$_POST["tsub_name_b"]."'";
	  $strSQL2 .=",'".$_POST["tcradit_b"]."','".$_POST["tGrade_bachelor"]."') ";
	$objQuery = mysql_query($strSQL2)or die ("Error Query [".$strSQL2."]");	
		}