<html><body><h2>Radio 单选按钮</h2><p><strong>input type="radio"</strong> 定义了一个单选按钮：</p><form action="/action_page.php"> <input type="radio" id="male" name="gender" value="male"> <label for="male">Male</label><br> <input type="radio" id="female" name="gender" value="female"> <label for="female">Female</label><br> <input type="radio" id="other" name="gender" value="other"> <label for="other">其他</label><br><br> <input type="submit" value="提交"></form> </body></html>