ช่วยทีครับ insert ข้อมูลหลายๆ record แบบ array ไม่ได้ครับ

for($i=0;$i<count($_POST["check"]);$i++){
			if($_POST["check"][$i]!="")
		{
  
			$strSQL = "INSERT INTO activity ";
			$strSQL .="(id_std,check)";
			$strSQL .="VALUES ";			
			$strSQL .="('".$_POST["id_std"][$i]."','".$_POST["check"][$i]."') ";
		
		
  mysql_select_db($database_localhost, $localhost);	
  $Result1 = mysql_query($strSQL, $localhost) or die(mysql_error());
		}

 <?php $i=1; do { ?>
		       <tr>
		         
		         
		         <td width="151" align="center"><?php echo $row_student['code_student']; ?></td>
		         <td width="201" align="center"><?php echo $row_student['name_student']; ?></td>
		         <td width="110" align="center"><?php echo $row_student['id_student']; ?></td>
		         <td width="46" align="center"><label for="checkbox"></label>
		           <input type="checkbox" name="check[]" id="check<?=$i;?>" value="1" onchange="true">
		           <input name="id_std[]" type="hidden" id="id_std<?=$i;?>" value="<?php echo $row_student['id_student']; ?>" />
		           <input name="time[]" type="hidden" id="time<?=$i;?>" value="<? echo date("Y-m-d/H:i");?>" /></td>
		         <td width="46" align="center">&nbsp;</td>
		         <td width="91" align="center">&nbsp;</td>
		         
		         
	          </tr>
		       <?php $i++; } while ($row_student = mysql_fetch_assoc($student)); ?>