Message in Chinese (Simplified) (中文(简体))
MC3089: 对象“<var>Object Name</var>”已经具有子级且无法添加“<var>X</var>”。“<var>Object Name</var>”只能接受一个子级。
Unlocalized message
MC3089: The object '<var>Object Name</var>' already has a child and cannot add '<var>X</var>'. '<var>Object Name</var>' can accept only one child.
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