不区分大小写，单双引号，
<html><head><title>初识HTML</title></head><body><h1>Hello world!</h1><img src = 'OIF-C.jfif'/></body>
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<head><meta charset="UTF-8"><!-- 兼容性 --><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>家人们，谁懂！</title>
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<body><img src="../img\news_logo.png">新浪>正文<h1>焦点访谈</h1><hr>2023.8.8<hr>
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<html><head>新浪网<style>#time{color: rgb(222, 218, 218);}#where{font-size: 15 px;}a{color: black;/* 去除下划线 */text-decoration: none;}p{text-indent: 35px;line-height: 35px;}#编辑{text-align: right;}</style></head><body><img src="../img/news_logo.png"><a href="https://www.cctv.com/" target="_self">新浪</a> >正文<hr><span id="time">2023.8.8</span> <span id = "where"> <a href="https://www.cctv.com/" target="_blank">央视网</a> </span><hr><!-- 正文 --><video src="../video/1.mp4" controls width="500px"></video><audio src="../audio/1.mp3" controls></audio><p><b>嘉宝啊</b>哇哇<strong>牛蛙</strong> 哇哇哇哇哇哇哇哇哇哇哇哇哇哇哇哇哇1哇哇哇哇哇哇哇哇哇哇哇哇哇哇哇哇dskjflkajs。</p><p>然后呢</p><img src="../img/7.jpg"><p>over</p><p id="编辑">责任编辑：陈锐</p></body>
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<html><head>新浪网<style>#time{color: rgb(222, 218, 218);}#where{font-size: 15 px;}a{color: black;/* 去除下划线 */text-decoration: none;}p{text-indent: 35px;line-height: 35px;}#编辑{text-align: right;}#center{width: 65%;margin:0 auto;}</style></head><body><div id="center"><img src="../img/news_logo.png"><a href="https://www.cctv.com/" target="_self">新浪</a> >正文<hr><span id="time">2023.8.8</span> <span id = "where"> <a href="https://www.cctv.com/" target="_blank">央视网</a> </span><hr><!-- 正文 --><video src="../video/1.mp4" controls width="500px"></video><audio src="../audio/1.mp3" controls></audio><p><b>嘉宝啊</b>哇哇<strong>牛蛙</strong> 哇哇哇哇哇哇哇哇哇哇哇哇哇哇哇哇哇1哇哇哇哇哇哇哇哇哇哇哇哇哇哇哇哇dskjflkajs。</p><p>然后呢</p><img src="../img/7.jpg"><p>over</p><p id="编辑">责任编辑：陈锐</p></div></body>
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<html><head><title>表格</title><style>tr{text-align: center;}</style></head><body><table border="1px" cellspacing="0" width="600px"><tr><th>序号</th><th>品牌</th><th>图标</th></tr><tr><td>1</td><td>华为</td><td><img src="../img/huawei.jpg"></td></tr><tr><td>2</td><td>阿里</td><td><img src="../img/alibaba.jpg"></td></tr></table></body>
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<html><head><title>表单</title></head><body><form action="" method="get">用户名：<input type="text" name="username">密码：<input type="text" name="password"><input type="submit" value="提交"></form></body>
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<html><head><title>表单</title></head><body><form action="" method="get">用户名：<input type="text" name="username"><br><br>密码 ：<input type="password" name="password"><br><br>性别 ：<label><input type="radio" name="gender" value="1">男 </label><label><input type="radio" name="gender" value="2">女 </label><br><br>科目 ：<label><input type="checkbox" name="subject" value="java">java</label><label><input type="checkbox" name="subject" value="SQL">SQL</label><label><input type="checkbox" name="subject" value="web">web</label><br><br>文件 ：<input type="file" name="file"><br><br>日期 ：<input type="date" name="date"><br><br>时间 ：<input type="time" name="time"><br><br>日期时间： <input type="datetime-local" name="datetime"><br><br>年龄 ：<input type="number" name="age"> <br><br>邮件 ：<input type="email" name="email"> <br><br>隐藏 ：<input type="hidden" name="hidden"><br><br>学历 ：<select name="degree"><option value="">请选择</option><option value="1">大专</option><option value="2">本科</option><option value="3">nice</option></select><br><br>描述 ：<textarea name="description" cols="30" rows="10"></textarea><br><br><input type="submit" value="提交"><input type="button" value="未知"><input type="reset" value="重置"></form></body>
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