Check out example codes for "fusion de cellule html". It will help you in understanding the concepts better.

Code Example 1

<style>
td,th{border:1px black solid; padding: 15px; text-align:center;}

table{border-collapse:collapse ;margin: 30px;}
</style>



<table>
            
            <thead>
              <tr>
                <th>Prénoms</th>
                <th>Noms</th>
                <th>Célibataire</th>
                <th>Couple</th>
                
              </tr>
            </thead>
            
            <tbody>
              <tr>
                <td rowspan=>Pierre</td>   
                <td rowspan=2>jardinier</td>
                <td>oui</td>
                <td>non</td>
              </tr>
              <tr>
                <td>Clarisse</td>
                <td>vendeuse</td>
                <td>non</td>
                <td>oui</td>
              </tr>
               <tr>
                <td>Bernard</td>
                <td colspan="">Politicien</td>
                <td colspan="2">??</td>
              </tr>
            </tbody>
            
            <tfoot>
               <th>Prénom</th>
               <th>Profession</th>
               <th>Célibataire</th>
              <th>Couple</th>
            </tfoot>
            
           </table><br/>
        
        <table>
          <tr>
            <th>Prénom</th>
            <td>Pierre</td>
             <td>Simon</td>
             <td>Yves</td>
          </tr>
          
          <tr>
            <th>Profession</th>
            <td>Jardinier</td>
             <td>Ecrivain</td>
             <td>Politicien</td>
          </tr>
          <tr>
            <th>Célibataire</th>
            <td>oui</td>
             <td>non</td>
             <td rowspan="2">??</td>
          </tr>
          <tr>
            <th>Couple</th>
            <td>non</td>
             <td>oui</td>

          </tr>
          
        </table>

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