Wukong looked at all the empty peach trees. He shook his head. " I'm in big trouble" .
悟空看着所有空空荡荡的桃树，摇了摇头：" 我惹了大麻烦了。"
英语百科
Null graph
（重定向自Empty tree）
In the mathematical field of graph theory, the term "null graph" may refer either to the order-zero graph, or alternatively, to any edgeless graph (the latter is sometimes called an "empty graph").