<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <table>
        <tr>
            <td>1a</td>
            <td>1b</td>
        </tr>
        <tr>
            <td>2a</td>
            <td>2b</td>
        </tr>
    </table>
</body>
<body>
    <table>
        <thead>
            <tr>
                <th>first name</th>
                <th>last name</th>
            </tr>
        </thead>
        <tr>
            <td>john</td>
            <td>doe</td>
        </tr>
        <tr>
            <td>jane</td>
            <td>doe</td>
        </tr>
    </table>
</body>
<body>
    <table>
        <thead>
            <tr>
                <th colspan="3">members</th>
            </tr>
        </thead>
        <thead>
            <tr>
                <th>id</th>
                <th>first name</th>
                <th>last name</th>
            </tr>
        </thead>
        <tbody>
            <tr>
                <td>1</td>
                <td>john</td>
                <td>doe</td>
            </tr>
        </tbody>
        <tbody>
            <tr>
                <td>2</td>
                <td>jane</td>
                <td>doe</td>
            </tr>
        </tbody>
    </table>
</body>
<body>
    <table>
        <thead>
            <tr>
                <th colspan="3">members</th>
            </tr>
        </thead>
        <thead>
            <tr>
                <th>id</th>
                <th>full name</th>
                <th rowspan="3"></th>
            </tr>
        </thead>
        <tbody>
            <tr>
                <td>1</td>
                <td>john doe</td>
            </tr>
        </tbody>
        <tbody>
            <tr>
                <td>2</td>
                <td>jane doe</td>
            </tr>
        </tbody>
    </table>
</body>
</html>