<html><head><style>table, th, td { border: 1px solid black;}</style></head><body><h1>th 元素</h1><p>th 元素定义表格中的标题单元格：</p><table> <tr> <th>Month</th> <th>Savings</th> </tr> <tr> <td>January</td> <td>$100</td> </tr> <tr> <td>February</td> <td>$80</td> </tr></table></body></html>