HTML Tablo - Satırları Birleştirmek

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<!DOCTYPE html>
<html>
<head>
<style>
table, th, td {
    border: 1px solid red;
    border-collapse:collapse;
}
th, td {
    padding: 20px;
}
</style>
</head>
<body>

<table style="width:100%">
  <tr>
    <th>Ad</th>
    <td>Ali Veli</td>
  </tr>
  <tr>
    <th rowspan="2">Telefon</th>
    <td>23344554</td>
  </tr>
  <tr>
    <td>55566778</td>
  </tr>
</table

</body>
</html>