activities related to services display properly

I want to store related activities of services

<form method='post' id='userform' action='arrayvalue.php'> <tr>
<td>Trouble Type</td>
<br>
<td>
 <input type='checkbox' name='servicevar[]' value='tds'>tds<br>    <br>

<input type='checkbox' name='activityvar[]' value='One'>Return<br>
<input type='checkbox' name='activityvar[]' value='Two'>Filling<br>
<br>


 <input type='checkbox' name='servicevar[]' value='Gst'>Gst<br>    <br>
<td>

<input type='checkbox' name='activityvar[]' value='One'>Return<br>
<input type='checkbox' name='activityvar[]' value='Two'>Filling<br>
<br>
</td> </tr> </table> <input type='submit' name="submit" class='buttons'> 

     <?php if(isset($_POST[submit]) {
                     $activity = $_POST['activityvar']; 
                     $service = $_POST['servicevar'];

    foreach ($service as $key => $value) {
            echo ($value);
             echo "<br>";

    foreach ($activity as $key => $value) {
            echo ($value);
            echo "<br>";
            }
          }
       }

MY OUTPUT:

• tds

  • one
  • two
  • one
  • two

• Gst

  • one
  • two
  • one
  • two

Expected Output:

• tds
  • one
  • two
• Gst
  • one
  • two

Thanksss...