php嵌套循环分类怎么写---求大神帮帮忙呀！

Question

鼠标悬停的时候，自动显示大分类下的小分类。(JS已经写出来了，就是php部分不会嵌套)

 <li class="nav-sub" data-tips="sub-school">
                    <a href="<{:U('Product/products')}>" class="tit">销售与支持</a>
                    <div class="nav-line poa"></div>
                        <dl class="child cf child_pro">
                            <dd class="fl">
                                <h1><a href="">产品-1</a></h1>
                                <h1><a href="">产品-2</a></h1>
                            </dd>
                            <div class="fr child_dt">
                                <div class="child_p">
                                    <img src="__CN__/images/nav_pic.png" width="351" height="217" />
                                    <h5 class="cf">
                                        <a href="javascript:;" class="fl">G</a>
                                        <a href="javascript:;" class="fl">G</a>
                                        <a href="javascript:;" class="fl">G</a>
                                    </h5>
                                </div>      
                                <div class="child_p">
                                    <img src="__CN__/images/nav_pic.png" width="351" height="217" />
                                    <h5 class="cf">
                                        <a href="javascript:;" class="fl">L</a>
                                        <a href="javascript:;" class="fl">L</a>
                                        <a href="javascript:;" class="fl">L</a>
                                    </h5>
                                </div> 
                            </div>
                        </dl>
                </li>

Answer 1

上面图片发错了