将克隆的子节点附加到克隆节点

Presume the following XML:

假设以下XML:

<outer>
    <entity>
        <id>123</id>
        <subnode1>
        <subnode2>
    </entity>
    <entity>
        <id>124</id>
        <subnode1>
        <subnode2>
    </entity>
</outer>
<outer>