!怎样在网页正中间或最下面加图片(代码)

求助!怎样在网页正中间或最上面加图片(代码)
<img src="图片地址"; width="480" height="360">
比如说这个代码 加的图片 都在网页的页低~~

------解决方案--------------------
HTML code
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     <p class="title_box"> <img src="images/read_more_icon.gif" width="14" height="14" /><span class="title_text">Javascript介绍</span></p>
<p>&nbsp; </p>
    <p>&nbsp;</p>
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        <p>闲庭雨初歇,暮晚柳阴直,若烟丝丝弄碧。 
魂随飞絮飘千里,凝眸处,几许惆怅,盈满心头,不觉泪暗滴。
离别话,耳盘聚。牵愁动恨,悲欢多无奈。
难思量,皆随落花逐流水。

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     <p class="title_box"><span class="title_text"><img src="images/read_more_icon.gif" width="14" height="14" />Javascript发展</span></p>
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曾几时,饮月花深烟处,醉卧馨香闻幽兰。
曾几时,执手露桥听雨,紫花油伞遮缠绵。</p>
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     <li><a href="#" >实验五</a></li>
     <li><a href="#" >实验六</a></li>
     <li><a href="#" >实验七</a></li>
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      <p class="chapters_box">第一章</p>
      <p class="chapters_box_link"><a href="#" >1.1</a></p>
      <p class="chapters_box_link"><a href="#" >1.2</a></p>
      <p>&nbsp;</p>
      <p class="chapters_box">第二章</p>
      <p class="chapters_box_link"><a href="#" >2.1</a></p>
      <p class="chapters_box_link"><a href="#" >2.2</a></p>
      <p>&nbsp;</p>
      <p class="chapters_box">第三章</p>
      <p class="chapters_box_link"><a href="#" >3.1</a></p>
      <p class="chapters_box_link"><a href="#" >3.2</a></p>
      <p>&nbsp;</p>
      <p class="chapters_box">&nbsp;&nbsp;第四章</p>
      <p class="chapters_box_link"><a href="#" >4.1</a></p>
      <p class="chapters_box_link"><a href="#" >4.2</a></p>
      <p>&nbsp;</p>
      <p class="chapters_box">第五章</p>
      <p class="chapters_box_link"><a href="#" >5.1</a></p>
      <p class="chapters_box_link"><a href="#" >5.2</a></p>
      <p class="chapters_box_link"><a href="#" >5.3</a></p>
      <p class="chapters_box_link"><a href="#" >5.4</a></p>
      <p>&nbsp;</p>
      <p class="chapters_box">第六章</p>
      <p class="chapters_box_link"><a href="#" >6.1</a></p>
      <p class="chapters_box_link"><a href="#" >6.2</a></p>
      <p>&nbsp;</p>
      <p class="chapters_box">第七章</p>
      <p class="chapters_box_link"><a href="#" >7.1</a></p>
      <p class="chapters_box_link"><a href="#" >7.2</a></p>
      <p>&nbsp;</p>
      <p class="chapters_box">第八章</p>
      <p class="chapters_box_link"><a href="#" >8.1</a></p>
      <p>&nbsp; </p>
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